Category Archives: CDI

AWS: POC-How to Build WordPress web site in AWS Cloud/Network ?


Most of the Blogs on websites are operated by WordPress[WP] software which is developed in PHP. Even my site [vskumar.blog] is from this software. To setup the WP, there are tier based architecture/setup required. For PHP related software we can have a 2-tier architecture setup.

For detailed analysis and the required AWS components for setting up W, below blog you can visit/follow blog:
https://vskumar.blog/2018/12/31/2-aws-wordpresswp-infrastructure-creation-using-a-free-tier-account/

In this demo video the WP site building project was discussed with different design steps towards AWS components and it was demonstrated well by one of our [experienced IT Professional] students well.


These are weekly assignments they get and they need to prove by themselves with a demo in a team; like live environment how it happens in a typical project team. By attending this activity delivery on weekly basis, one will not get any fear/scareness on doing the live infra tasks. They will be habituated with the project activities when they join in real job. And they will be productive resources from day one onwards. These are the major benefits from my course.

Also, visit the below blog also:

https://vskumar.blog/2020/01/20/aws-devops-stage1-stage2-course-for-modern-tech-professional/

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

AWS: POC-How to do VPC Peering with 2 VPCs ?

When we have two networks in traditional methods, we used to do internal networking within the premises. And used those servers for Software APIs. Also the Sysadmin/DBAs/Network Admin role people used to manage them well. But in Cloud how to implement this kind of setup ?

In this POC project, it is well proven how we can create such kind of environment by using 2 VPCs and their peering with deeper analysis and the design steps of different services. And how the private subnet related Linux and Windows EC2s can be accessed by using NAT and Jump Servers?. And how to operate another VPC EC2 from one VPC EC2 ? Just watch this design steps analysis video from the below link:

In the below video a POC analysis is discussed with an Experienced Cloud/DevOps professional.

Watch the below video for How to config NATGATEWAY and use it for Private EC2 MySql config.

https://www.facebook.com/105445867924912/videos/977486682736825/

Also, visit the below blog also:

https://vskumar.blog/2020/01/20/aws-devops-stage1-stage2-course-for-modern-tech-professional/

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

AWS: Follow AWS SAA Best practices for interviews

In the following video the AWS SAA Best practices were discussed in detailed. These are useful for Cloud Architect/Engineer role job interview.

If you want to know why you need to learn and become/grow into Cloud/.DevOps Role, watch the below video:

For my Course details please see the below blogs and the videos.

https://vskumar.blog/2020/01/20/aws-devops-stage1-stage2-course-for-modern-tech-professional/

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

A quick review on DevOps Practices for DevOps Engineers/Practitioners

Watch this video.

DevOps Patterns
devops-process
  1. DevOps is a terminology used to refer to a set of principles and practices to emphasize the collaboration and communication of Information Technology [IT] professionals in a software project organization, while automating the process of software delivery and infrastructure using Continuous Delivery Integration[CDI] methods.
  2. The DevOps is also connecting the teams of Development and Operations together to work collaboratively to deliver the Software to the customers in an iterative development model by adopting Continuous Delivery Integration [CDI] concepts. The software delivery happens  in small pieces at different delivery intervals. Sometimes these intervals can be accelerated depends on the customer demand.
  3. The DevOps is a new practice globally adopted by many companies and its importance and implementation is accelerating by maintaining constant speed.  So every IT professional need to learn the concepts of DevOps and its Continuous Delivery Integration [CDI] methods. To know the typical DevOps activities by role just watch the video: https://youtu.be/vpgi5zZd6bs, it is pasted below in videos.
  4. Even a college graduate or freshers also need to have this knowledge or practices to work closely with their new project teams in a company. If a fresher attends this course he/she can get into the project shoes faster to cope up with the  experienced teams.
  5. Another way; The DevOps is an extension practice of Agile and continuous delivery. To merge into this career; the IT professionals  need to learn the Agile concepts, Software configuration management, Release management, deployment management and  different DevOps principles and practices to implement the CDI patterns. The relevant tools for these practices integration. There are various tool vendors in the market. Also open source tools are very famous. Using these tools the DevOps practices can be integrated to maintain the speed for CDI.
  6. There  are tools related with version control and CDI automation. One need to learn the process steps related to these areas by attending a course. Then the tools can be understood easily.  If one understands these CDI automation practices and later on learning the tools process is very easy by self also depends on their work environment.
  7. As mentioned in the above; Every IT company or IT services company need to adopt the DevOps practices for their customers competent service delivery in global IT industry. When these companies adopt these practices, their resources also need to be with thorough knowledge of DevOps practices to serve to the customers. The companies can get more benefit by having these knowledged resources. At the same time the new joinees in any company either experienced or fresher professional if they have this knowledge, their CTC in view of perks will be offered more or with competent offer they may be invited to join in that company.
  8. Let us know if you need  DevOps training  from  the IT industry experienced people; which includes the above practice areas to boost you in the IT industry.

Training will be given by 3 decades of Global IT experienced  professional(s):

https://www.linkedin.com/in/vskumaritpractices

For DevOps roles and activities watch my video:

Folks, I also run the DevOps Practices Group: https://www.facebook.com/groups/1911594275816833/?ref=bookmarks

There are many Learning units I am creating with basics. If you are not yet a member, please apply to utilize them. Read and follow the rules before you click your mouse.

For contact/course details please visit:

https://vskumarblogs.wordpress.com/2016/12/23/devops-training-on-principles-and-best-practices/

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AWS/DevOps: POC-Infra and DevOps Automation

In the Cloud/DevOps modern technology, the Automation became popular to save the manpower and the IT Budget. Among the IT Roles these roles are going to be the demanding ones always. With any technology or tools need to be followed this process.

What areas can be used for automation ?

What are the technology/tools can be used ?

In the below video a POC analysis is discussed with an Experienced Cloud/DevOps professional.

Also, visit the below blog also:

https://vskumar.blog/2020/01/20/aws-devops-stage1-stage2-course-for-modern-tech-professional/

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

How to join in my groups of different practices and watch some [15%] of my past sessions on Cloud/DevOps Architects building course ?

Please follow the below guidelines to apply.

What is Site Reliability Engineering [SRE]?

What is Site Reliability Engineering [SRE]?
What are SRE major components ?
What is Platform Engineering [PE] ?
How the Technology Operations [TO] is associated with SRE ?

What the DevOps-SRE diagram contains ?
How the SRE tasks can be associated with DevOps ?
How the Infrastructure activity can be automated for Cloud setup ?
How the DevOps loop process works with SRE, Platform Engineering[PE] and TO ?
What is IAC for Cloud setup ?
How to get the requirements of IAC in a Cloud environment ?
How the IAC can be connected to the SRE activity ?
How the reliability can be established through IAC automation ?
How the Code snippets need to/can be planed for Infra automation ?
There are many FAQs can be identified with this video.

For all the answers you need to watch the below discussion video:

If you are an original IT profiled person and trying for SRE roles globally in any country, you can contact for a mock interview. You need to follow the pre-requisites:

1. Connect me on LinkedIn to very you.

2. Share your profile.

3. Fix up a call to discuss on the mock interview effort/phases.

Please note its chargeable for each phase.

NOTE: I ENCOURAGE THE ORIGINAL PROFESSIONALS ONLY TO GROW/SUSTAIN IN THE CURRENT/FUTURE IT BY LEARNING.

I DO NOT DO PROXY INTERVIEWS. I AM ALLERGIC FOR THOSE ATTITUDES/PRACTICES. YOU NEED NOT CALL ME FOR THAT NEED.

Also, visit for some more details:

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

DevOps: What are the Differences between containers and VMs ?

What are the Differences between containers and VMs ?

During Deployment activity phase the environment building is part of the DevOps practices.

In traditional method we used to spend lot of time for this task. But when it came with VMs and containers, it is easy and in minutes the environments can be prepared using the IAC.

The containers became very popular for building the test environments. Let us say you want to build a MYSQL server, the solutions is; simply try to understand its environment and pull one Docker image which has the MYSQL. Then use it in that network environment.

When we talk about the VMs and Containers one need to understand their differences. I have made a video for learners:

If you are a Docker learner, then try to build the MYSQL container from the below specifications:

DevOps: Advanced DevOps Practices/Processes-2 [DevSecOps]

In continuation of my previous blog on; DevOps:Advanced DevOps Practices/Processes-1:
Following are the some of the DevOps concepts, a Practitioner need to practice.

What is the goal of DevSecOps?

The goal of DevSecOps is to decrease time to market while cutting the costs of development and remediation, while improving overall application security.

How it can be performed ?:

If the appropriate, automated security vulnerability and configuration scanning tools are deployed, developers with varying skill sets and experience can find and fix security problems as they occur.

How to motivate developers?:

Teaching developers on secure coding practices is still essential,  as it is monitoring and protecting the production environment.

How to achieve it?:

By integrating automated application security testing as part of the moving into DevSecOps practices, teams can complete a DevOps security checking that addresses the challenges associated with developing secure applications in agile environments.

How to apply checkpoints?:

There are tools to verify the above checks.

I have discussed some of the relevant points on this subject in the below video session:

DevOps: Advanced DevOps Practices/Processes-1

DevOps:Advanced DevOps Practices/Processes-1:
Following are more than the DevOps concepts, a Practitioner need to practice. So we can call them as part of Advanced DevOps practices also.

I have made a material and a discussion video which answers the below questions topic wise.

  1. What are the DevOps Loop activities ?
  2. What are the DevOps Patterns and Practices as per the Gartner ?
  3. What are the processes ?
  4. What is Culture in DevOps ?
  5. What is Technology ?
  6. Who are the People ?
  7. What are the bodies of Knowledge in DevOps in view of Agile and Scrum ?
  8. How the IT service management [ITSM] can be aligned with DevOps/Agile ?
  9. How the Quality Management Systems [QMS] can be connected with DevOps ?
  10. How the Automated testing life cycle can be connected ?
  11. How the Cloud Security is connected with DevOps ?
  12. How the Microservices and SOA are connected with DevOps ?
  13. What is Site Reliability Engineering [SRE] and how it is connected with DevOps ?
  14. What is Continuous Delivery Matrix Index [CDI] in DevOps ?
  15. How the CDI is connected with 5 maturity levels during practices ?

The attached Video has the discussions on the above topics.

How to Create a Learning Organization during DevOps Practices implementation ?

Create Learning-DevOps organization.png

If you are keen in learning DevOps Practices as on latest, you can apply to join in my group: https://www.facebook.com/groups/1911594275816833/

Please note there are rules to follow.

For DevOps roles and activities watch my video:

For contact/course details please visit:

https://vskumarblogs.wordpress.com/2016/12/23/devops-training-on-principles-and-best-practices/

Contact for AWS DevOps Engineer – Professional certification. Very few people globally covering the complete syllabus like I have explained from the AWS Exam guide. If interested please ping me in FB with your profile URL. Please note I coach only the global working IT Professionals.  Hence Profile URL is mandated to know your background.

Watch the below 50 minutes video for the above analysis:

2. AWS POC : WordPress[WP] infrastructure creation using a free tier account

With reference to my previous blog on:
1. AWS:How to create and activate a new account in AWS ?
https://vskumar.blog/2018/09/01/1-awshow-to-create-and-activate-a-new-account-in-aws/

I have made a scenario based “AWS services usage” blog in this content. Which can be considered as a Proof of Concept [POC] Project also.

If you are new for cloud technology, I have made a video cum blog for you to understand its initiation/evaluation concepts. This video is more useful for PMs/Cloud Architects/DevOps role based people.

For video Visit:

For the above video’s blog:

https://vskumarcloudblogs.wordpress.com/2016/11/30/how-to-initiate-a-cloud-transformation/

Now, let us move forward with this blog content.

In this AWS exercise, I have described/demonstrated on WordPress[WP] infrastructure creation using a free tier account.

At the end of this blog a micro level lab practiced steps are copied and a recorded video is there on my channel.

I would like to explain from architecture/design perspective through this blog, before you go to Lab steps.
After doing this exercise, simply and finally we can come into the following conclusions:

a) Creating a blogging infrastructure can be fully automated through AWS services.
b) Infrastructure can be created at any time on-demand without any up-front
commitment for how long we will use it in AWS.
c) We can pay for our infrastructure depending on how many hours we use it.
d) Infrastructure consists of several parts,
such as; i) virtual servers, ii) load balancers, and iii) databases.
e) Infrastructure can be deleted with one click without costing to us.

This process is powered by AWS automation. So it will not be billed to our free tier account after deletion!!.

First let us analyze on WP and its components.

How a WordPress infrastructure can be planned?

Assume we have a startup company, which publishes more white papers and  blogs.

Assuming; our startup company currently uses WordPress[WP]  to host over 500 blogs on our own servers.  The blogging infrastructure must be highly available, because customers don’t tolerate outages of any servers.  To evaluate whether a migration is possible through AWS services, we need to do the following three Activities planning and try out with AWS free-tier account:

A) Set up a highly available blogging infrastructure in AWS.
B) Estimate monthly costs of the infrastructure.

C) Finally, Delete our blogging infrastructure to save cost from free-tier account.

For our understanding on WP;

  • WordPress[WP] is written in PHP and uses a  MySQL database to store data.
  • Apache is used as the web server to serve the blog pages.
  • With this information in our mind, we map our requirements to AWS services  to test the infrastructure creation.

Now, let us analyze on “what are the AWS services required for our WP test infrastructure?”.

We need  the below AWS services to do this activity:
I. Elastic Load Balancing (ELB),
II. Elastic Compute Cloud (EC2),
III. Relational Database Service (RDS) for MySQL and
IV. Security groups.

Let us analyze what are the functions/benefits of  these AWS services.

I. Elastic Load Balancing (ELB):

AWS offers a load balancer as a service.
The Elastic Load Balancer (ELB) distributes traffic to a bunch of servers behind it in a cloud environment. It’s highly available by default.

Let us assume our startup company’s blogs are published globally. From many countries these can be accessed by the users. Assume there are lot of users access this content globally. Then in traditional method your load is not balanced without  having physical servers connected through VPNs/networks, etc. in different locations. Think about the Hardware/Software/maintenance/FMG cost for this traditional infrastructure. We can not think it being a startup company to spend much. No way!! Hence we need to depend on cloud service provider.

With AWS ELB, this can be balanced by distributing the blog users traffic to different virtual servers under cloud environment. To denote this distributed load balancing  architecture, I have collected a diagram  on;

WordPress infrastructure and Load Balancing through ELB AWS service.
Which is pasted here for your clarity on the ELB function.

WP-Infra-ELB-load Distribution.png

II. Elastic Compute Cloud (EC2):

It is A virtual server which is provided by the Elastic Compute Cloud (EC2) service of AWS. We will use a Linux server with an optimized distribution called Amazon Linux to install Apache, PHP, and WordPress during our exercise. Please note; we are not limited to Amazon Linux only; we can also choose Ubuntu, Debian, Red Hat, or Windows. Virtual servers can fail at any time, so we need at least two of them for contingency planning. The load balancer will distribute the traffic between them. The beauty of AWS service in case of a server failure is; the load balancer will stop sending traffic to the failed server, and the remaining [contingency] server will need to handle all the requests until the failed server is replaced. Let us not worry on this communication! You will be intimated the status through alerts.

A sample architecture diagram is pasted here FYI with two EC2 instances.

EC2-two instance-ELB-Scenario.png

III. Relational Database Service (RDS) for MySQL:

WordPress relies on the popular MySQL database. AWS provides MySQL as a Relational Database Service (RDS). We can choose the database size (like; storage, CPU, RAM), and RDS takes care of the rest (backups, updates). RDS can also provide a highly available MySQL database by replication. In traditional [non-cloud] model we had the similar setup. It occurs huge costing. By using AWS cloud services this can be easily maintained with minor costing only.

On this context; from the below diagram we can see the MYSQL features from AWS services offering.

AWS-MYSQL-RDS-features

V. Security groups:

In every application architecture we need to have the security features in place. Either these can be embed in the applications or through security tools it can be applied. So the entire architecture is protected that way.

But in cloud services many providers provide these services differently with their services offering.

The Security groups are a fundamental service of AWS to control network traffic like a firewall in traditional systems. Security groups can be attached to a lot of services like ELB, EC2, and RDS. For example; with security groups, we can configure our load balancer as below:

It only accepts requests on port 80 from the internet. Web servers only accept connections on port 80 from the load balancer. And MySQL only accepts connections on port 3306 from the web servers. If we want to log in to our web servers via SSH, we must also open port 22. Similar ways the architecture setup can be configured.

FYI, I have considered a diagram from AWS docs; which denotes a typical AWS multi-tier approach security services with a Firewall:

AWS-Security mulit-tier aproach.png

As shown in the above diagram, A security group acts as a virtual firewall for our instance to control inbound and outbound traffic. When we launch an instance in a Virtual Private Cloud[VPC], we can assign the instance to up to five security groups. It means in any VPC  AWS provides five different security groups.

So, now what is our start company plan for security?:

Let us assume our startup company’s blogging infrastructure consists of two load-balanced web servers running a) WordPress and b) a MySQL database server.

The following tasks are performed automatically in the background through AWS:

  1. Creating an ELB.
  2. Creating a RDS MySQL database.
  3. Creating and attaching security groups.
  4. Creating two web servers.
  5. Creating two EC2 virtual servers.
  6. Installing Apache and PHP via yum.
  7. Install php, php-mysql, mysql, httpd.
  8. Downloading and extracting the latest version of WordPress from http://wordpress.org/latest.tar.gz   
  9. Configuring WordPress to use the created RDS MySQL database 
  10. Starting Apache. 

Before going to the above steps, I would like to show the below diagram for your understanding on “The setup of WP hosting on AWS”. You can download it through the URL given and see it as an image file for your understanding.

AWS-WP-Hosting setup

Now, let us recap our beginning conclusions for this blog. We need to do the below activities till end of the exercise.

  1. Creating a blogging infrastructure.

  2. Analyzing costs of a blogging infrastructure.

  3. Exploring a blogging infrastructure.

  4. Shutting down a blogging infrastructure.

  5. Deleting infrastructure from AWS Account.

1. What actions we need to consider for Creating blogging infrastructure in AWS?: To create the blogging infrastructure we need the below steps to follow on AWS console.

Note: Please note time to time the screen flows [micro level steps] might change on AWS, but the process should be the same to understand on creation of this WP infra.

  1. Open the AWS Management Console at https://console.aws.amazon.com.
  2. Click Services in the navigation bar, and click the Cloud-Formation service.
  3. Click on Create Stack to start the four-step wizard.

Now we will see what are these 4 steps wizard process it contains.

I. Creating a blogging infrastructure: Step 1 of 4

You need to name your infrastructure. Enter “wordpress” as the Name. For Source option, select and  Specify an Amazon S3 Template URL as shown in the screen [lab exercise screen]. Copy this URL and save somewhere in a text file for future reference/usage. About this process, during lab demo you will understand clearly.

II. Creating a blogging infrastructure: Step 2 of 4

Click Next to set the KeyName to “vskumarkey” [example only, you can give any name], for Step 2 of 4. Click Next to create a tag for our infrastructure into next screen. These steps can be seen clearly in lab practices steps.

III. Creating a blogging infrastructure: Step 3 of 4

A tag consists of a key-value pair and can be used to add information to all parts of our infrastructure. We can use tags to differentiate between testing and production resources, add the cost center to easily track costs in our organization [if any], or mark resources that belong to a certain application if we host multiple applications in the same AWS account.

In this example, we will use a tag to mark all of our resources that belong to the “wordpress system”. This will help us later to easily find our infrastructure. Use “system” as the key and “wordpress” as the value.  Click Next. Finally, we will see a confirmation page for Step 4 of 4. For clarity look into lab steps.

IV. Creating a blogging infrastructure: Step 4 of 4

In the Estimate Cost row, click Cost. This will open a new browser tab in the background. Keep this browser open only. We will come back to this screen later. Switch back to the original browser tab and click Create. We can see next Review screen in the next page.

Now, our infrastructure will be created. This Review screen shows that wordpress is in the state of CREATE_IN_PROGRESS. It takes 15-20 mts to complete this process.

Now, please take a look at the result by refreshing the page. Select the “WordPress” row, where Status should be CREATE_COMPLETE. If the status is still CREATE_IN_PROGRESS, be patient until the status becomes CREATE_COMPLETE.

Switch to the Outputs tab [below part of the screen], which is the Blogging infrastructure result. There we can find the URL to our “wordpress system”; click it to visit the system.

What is AWS Automation here?:

As we have discussed in the beginning of this blog, one of the key concepts of AWS is automation. We can automate everything. In the background, our blogging infrastructure was created based on a blueprint with its automation. So the above mentioned [10] tasks have been performed in the background by AWS cloud formation service. You can see the beauty of this automation during lab demonstration.

Blogging infrastructure result:

Now we’ve created our blogging infrastructure, let us take a  look at it. Our infrastructure consists of the following as we discussed in this blog:

  • Web servers
  • Load balancer
  • MySQL database

Now; we will  use the resource groups feature of the Management Console to get an overview.

Exploring the created WP Blogging  infrastructure

Now let us understand;

What is Resource Group in AWS?:

  1. A resource group is a collection of AWS resources.
  2. Resource is an abstract term for something in AWS like an EC2 server, a security group, or a RDS database.
  3. Resources can be tagged with key-value pairs. In such case; let us note we can have more than one key-value pairs.
  4. Resource groups specify what tags are needed for a resource to belong to the group.
  5. Furthermore, a resource group specifies the region(s) where the resource should reside in. It means globally these resource groups can be deployed for its functioning. 
  6. We can use resource groups to group resources if we run multiple systems in the same AWS account. This way we are sharing the resources among the projects or app architectures.
  7. Let us note that we have tagged the blogging infrastructure with the key “system” and the value “wordpress”.
  8. As an example; from now on, we will use this notation for key-value pairs: (system:wordpress). We’ll use that tag to create a resource group for our WordPress infrastructure.  For further clarity please look into the lab steps/video.

Now let us understand;

How to create  a resource group in AWS?:

    1. In the AWS part of the top navigation bar, click Create a Resource Group.
    2. Set Group Name to “wordpress” or whatever you like.
    3. Add the tag system with the value wordpress.
    4. Select the region N. Virginia [for example]. [I have used my existing account]
    5. Save the resource group.
    6. It will take you to next screen shown in next page. Follow the below steps.

How to see the Blogging infrastructure web servers via resource groups details?:

  1. Select Instances under EC2 on the left to see the web servers.
  2. By clicking the arrow icon in the Go column, you can easily jump to the details of a single web server. 
  3. Now, You are  looking at the details of your web server, which is also called an EC2 instance.

Details of web servers running the blogging infrastructure:

  1. On this screen the interesting/important details are as below:
  • Instance type: It tells us about how powerful your instance is.
  • Public IP address: The IP address that is  reachable over the internet. You can use that IP address to connect to the server via SSH.
  • Security groups: If you click on View Rules, you’ll see the active firewall rules like the one that enabled port 22 from all sources (0.0.0.0/0).
  • AMI ID: Let us recollect that we used the Amazon Linux operating system (OS). If you click the AMI ID, you will  see the version number of the OS, among others.  

We also need to know the utilization of webservers, like how we used to monitor in live [for production boxes].

Looking for webserver utilization and metrics in AWS:

2. In the screen; Select the Monitoring tab to see how your web server is utilized.

3. This will become part of our job: really knowing how the infrastructure is doing.

4. AWS collects some metrics and shows them in the Monitoring section. If the CPU is utilized more than 80%, you should add a third server to prevent page load times from increasing.

Now let us understand on;

How to check the Blogging infrastructure load balancer via resource groups?:

  1. We can find the load balancer by selecting Load Balancers under EC2 on the left to the page.
  2. By clicking the arrow icon in the Go column, you can easily jump to the details of the load balancer.
  3. Now, we are looking at the details of your load balancer.
  4. Here; the most interesting part is, “How the load balancer forwards traffic to the web servers?“.
  5. The blogging infrastructure runs on port 80, which is the default HTTP port.
  6. The load balancer accepts only HTTP connections to forward to one of the web servers that also listen on port 80.
  7. The load balancer performs a health check on the virtual servers attached.
  8. Both virtual servers are working as expected, so the load balancer routes traffic to them.    

How to check the MySQL server ?:

Details of the MySQL database which stores data for the blogging infrastructure

  1. Now; let’s look at the MySQL database. You can find the database in a resource group named wordpress.
  2. Select DB Instances under RDS at left.
  3. By clicking the arrow icon in the Go column, you can easily jump to the details of the database.
  4. Now the details of our MySQL database are shown in the screen.
  5. The benefit of using RDS is that we no longer need to worry about backups because AWS performs them automatically.
  6. Updates are performed by AWS in a custom maintenance window. Keep in mind that you can choose the right database size in terms of storage, CPU, and RAM, depending on your needs.
  7. AWS offers many different instance classes, from 1 core with 1 GB RAM up to 32 cores with 244 GB RAM.

Note: I would like to emphasize to compare the traditional [non-cloud] approach. We were using scheduler to backup the DB periodically. Some times we used to shutdown the live systems to take the backups. So, from AWS RDS services we do not need interruption to the business to take backup, RDS takes care everything. We can save the role of sysadmin/DBA while using the AWS services. This way the resources efforts and business services down time are saved.

As we planned three activities for this whole exercise as on now; we have completed the activity of “A) Set up a highly available blogging infrastructure in AWS.”

Now, we are going to work on; “B) Estimate monthly costs of the infrastructure.”

  1. As the  part of this exercise is’ cost estimation also need to be done.
  2. To analyze the cost of our blogging infrastructure, we will  use the AWS Simple Monthly Calculator.
  3. Recollect that we clicked the Cost link in the previous section to open a new browser tab.
  4. Now, switch to that browser tab, and you will see a screen as shown in the below  chart.
  5. To Estimate of our Monthly Bill, and expand the Amazon EC2 Service and Amazon RDS Service rows.

Now, Let us see and understand the below chart.

Blogging infrastructure cost calculation

Now it’s time to evaluate costs. We can see on How much does it cost?

  1. In this example, our infrastructure will cost is around $60 per month.
  2. Let us keep in mind that this is only an estimate.
  3. We are billed based on the actual usage till the end of the month.
  4. Everything is on-demand and usually billed by hours of usage or by gigabytes of usage.
  5. But what influences the usage for this infrastructure?

Let us analyze different situations and identify the costing parameters as below:

Traffic processed by the load balancer: Let us assume; Expect the costs to go down in during festival/vacation season like;  “December and the summer”. When the people are on vacation and not looking at our blogs.

Storage needed for the database: If our startup company increases the number of blogs, the database will grow, so the cost of storage will increase this way.

Number of web servers needed: A single web server is billed by hours of usage. If two web servers are not enough to handle all the traffic during the day, we may need a third server.  By default we need to keep in our AWS/EC2 setup. In that case, we will consume more hours of virtual servers.

Now we had a clear overview of the blogging infrastructure creation and its cost estimation/Analysis. Similar way you will be able to do for your AWS migration projects also.

Now; with reference to  the 3rd  step, it is time to shut down the infrastructure and complete our AWS migration evaluation exercise.

Let us recap our planned 3rd activity;

C) Finally, Delete our blogging infrastructure to save cost from free-tier account.

Now, go to the CloudFormation service in the Management Console and do the following:

  1. Select the WordPress row.
  2. Click Delete Stack, as shown in top of the screen.
  3. After you confirm the deletion of the infrastructure, it takes few minutes for AWS to delete all of the infrastructure’s dependencies.
  4. Please note; this is an efficient way to manage our infrastructure.
  5. Just as the infrastructure’s creation was automated, its deletion is also completely automated.
  6. You can create and delete infrastructure on-demand whenever you would like, and you only pay for infrastructure when you create and run it.  

<===== I copied the relevant lab practiced steps for your easy use ======>

These steps were used as on dated: 9th Sept 2018 on my free-tier account for student purpose.
The AWS might change its Screens flow or UI part time to time.
Hence from the above blog narration some detailed steps are given in the below lab practice steps for your easy use/practice.

1. Sign-in to your AWS console account from URL:
https://aws.amazon.com/

2. Login to the account.
3. Click on Services.
4. Please note we need to use Cloudformation service of AWS in this exercise.
Hence click on Cloudformation.
5. You will be shown the screen to create a new stack. Click on it. Note as mentioned in my blog it has 4 step process.
6. Now, select a sample template. Choose WordPress blog. It creates/shows the S3 template url.
7. Copy the S3 Template URL into a file for future usage.
8. Now, click on Next to go to next screen.
9. Under Specify Details columns, mention the details.
10. Please note my Infra name I want to give “wordpress”.
11. It has the predefined DB “wordpressdb”, I will keep it.
12. I can give DB Passwords, as required in the entry boxes/columns.
13. Dbuser “vskumarwp”. It has instance type t2.small.
14. Now, as you are aware we need to have the local SSH keys which we have created earlier. I have some keys I have selected one. [If you are new for this account, create the SSH keys…]
15. I need to give the range of IPs to be used for our wp servers.
I want to use 192.168.116.9/15.
16. Now, need to click on next…
Please note the above steps are required for you….

17. Let me give System as “worpress” and key as “system” as mentioned in my blog.
18. I want to skip ARN value in this exercise, due to as I mentioned in blog I would like to follow. I will not have any ARN, Hence monitoring is not mandated for me in this exercise. Then press “Next”.

19. Now, we will see the review screen as mentioned in Blog. On reveiw screen press Create button.
20. We are in creation process screen as mentioned in Blog.
CREATE COMPLETE IS DONE NOW.

21. Now let me click on my instance vskumarwp.

22. Now, go to the top navaigation bar and select the resource groups.
23. Select create resource group. You will get a new screen which has some entries and selections. Give tag key as “worpress” and press create group.
24. Next screen it shows wordpress as the resource group name.

25. Now, go to EC2 instance from the left side shown.
Now, you can see in bottom of the screen as mentioned in the blog.

26. I can see ELB by clicking on ELB option in the left panel.
Please note I have not given the ARN. Hence the Monitoring option is not selected.
Due to it might charge me.

27. You can see the cloud watch options through monitoring button in the below part of the screen.

28. Please note the security groups are attached by default.

29. Please note if I want to use this EC2 instance which is prepared for WP, I need to launch in AWS services live.
Which is going to be billed. Hence I will stop at this point.

30. The FINAL step is to delete the Instance of WP. I will go to cloudformation option.
Then it displays the current instance. I will select it and go to actions and select the DELETE STACK Option.
It prompts for ‘YES/NO’, Select Yes. It can take some time to perform deletion.

31. Once it is deleted it will comeback to the Stack creation screen.
Please note I have checked it, there are no existing instances in my current account.
We can see it as terminated instance.

32. So, this way we can create infra and delete it very easily.

33. So, let us have a final conclusion, section from blog.

34. Please call me if you need any coaching for AWS course….
THANKS FOR WATCHING MY VIDEOS/BLOGS ……..

 

Watch the below video on this blog Narration:

https://www.facebook.com/watch/?v=254567748762273

 

For the above steps a 40 mts videos has been made and hosted  on my channel. Please look into it also.

================= End of Lab practice ===============================>

 

Now, after doing all the above steps we can compare our conclusions mentioned in the beginning of this blog. I copied the same for your cross check!!

a) Creating a blogging infrastructure can be fully automated through AWS services.
b) Infrastructure can be created at any time on-demand without any up-front
commitment for how long we will use it in AWS.
c) We can pay for our infrastructure depending on how many hours we use it.
d) Infrastructure consists of several parts,
such as; virtual servers, load balancers, and databases.
e) Infrastructure can be deleted with one click without costing to us.
This process is powered by AWS automation. So it will not be billed to our free tier account after deletion.

I assume now, you are a fearless user of AWS to create the infrastructure through your free-tier account and delete and maintain the account without a cost to your CC/Account.

If you are interested to learn Virtualization with Vagrant visit:

1. Vagrant/Virtual Box:How to create Virtual Machine[VM] on Windows 10?:

Note to the reader of this blog:

If you are not a student of my class, and looking for it please contact me by mail with your LinkedIn identity. And send a connection request with a message on your need. You can use the below contacts. Please note; I teach globally.

Vcard-Shanthi Kumar V-v3

This blog is created as an video  also. There are series of videos made till end of the lab session. At the end,  the lab practices are also recorded for your use with your free AWS account.

 

 

 

 

For some more AWS Specimen POCs visit the below FB web pages:

Build Cloud Solution Architects

MicroServices and Docker

If you want to learn indepth Cloud/DevOps Architec role with Infra setup upto IAC Automation the following course can help you to convert into the demanding role:

https://vskumar.blog/2020/01/20/aws-devops-stage1-stage2-course-for-modern-tech-professional/

There are many global working professionals are inclined on this curriculum. Watch the videos and ping me on Facebook: https://www.facebook.com/shanthikumar.vemulapalli

3. AWS: How to create S3 Bucket and share object URL ?

In this blog, I have given the link to the discussion video:

a) Creating a Bucket on S3.

b) Uploading an Object.

c) Sharing the object URL.

d) Testing the object URL for its display in  Different Laptop.

Watch this attached video



AWS-SAA-Course

How a DevOps Architect role is different from A Cloud Architect ?

Many people might feel the Cloud Architect and DevOps Architect can play dual roles. As per my observation yes, many small and medium level organizations are utilizing the IT Professionals in the same manner. I wrote a blog for these roles segregation with their main Activities. I felt this might help to some of the practitioners.

With reference to my previous blog on Cloud Architect role comparison with DevOps, there were questions on DevOps architect role comparison.

https://vskumar.blog/2018/11/21/how-a-cloud-architect-is-different-from-devops-role/

Basically, A DevOps architect need to work on:

  1. Identifying the Sprint cycles for different projects.
  2. Identifying the different environments needs including the different test levels requirements.
  3. Plan/design the environment specifications to build Infrastructure As A Code [IAC] and guide the DevOps Engineers.
  4. At the same time he/she need to collaborate with the Cloud Architect to seek the permissions/approvals to utilize the cloud environment on these environmental requirements/setup.
  5. Both these architects need to measure the cost of this Infrastructure to estimate and get approval from the management.
  6. The DevOps Architect is also responsible to plan for different production deployments. He/She need to work together with the Cloud Architect to establish this setup.
  7. In the current trend the containerization is accelerating with Cloud technology. Both these architects need to keep working on these areas to reduce the Virtual Machines cost by replacing with containers. At the same time these two people need to think on converting the applications into Microservices slowly with the Agile methods. This will have easy maintenance in future and also the further cost can be reduced in view of infrastructure and the man power. And their guidelines need to submit to management as a proposal. These two people are also responsible to upgrade their teams skills on the new trends in Cloud technology.
  8. If you ask me the question who are the team members for these roles;
  9. DevOps Engineers will report to DevOps Architect.
  10. Cloud/system engineer reports to Cloud Architect.

So these architects need to manage their teams well in view of their skills augmentation and the tasks rolling as per the DevOps Speed/Velocity concepts.

What kind of IT Professionals can be converted into DevOps Architect ?

Basically, the DevOps activities are related to more on Practices and Culture. If your background is related to the below areas in the past, your profile might suit to convert by learning the above mentioned skills.

  • You might have worked on Deployment areas
  • Worked in release management
  • Worked in Development processes implementation areas.
  • You should be savvy in implementing the Agile/Scrum/Lean practices.
  • You should have worked as a Servant leadership role also. [Even as a Scrum master]. In many cases this role is responsible to mentor the teams on different practices implementation by gearing up the teams to follow DevOps Velocity.
  • You should have worked in Identifying the retrospective issues very well and implemented the improvements in different Sprint cycles.
  • He/she should be savvy in learning new technology and transform the knowledge to the teams well. This knowledge should be very simple on the tools features related areas and how they can utilize them in their setup ? How they can reduce the efforts and cost to the company with a ROI Demonstration. They need to prove it to management with a POC.
  • This person is responsible to show some ROI as Cloud Architect does it on DevOps New practices implementation.
  • The DevOps Architect reports to the DevOps Practices head or CIO or CTO. Where as the Cloud Architect reports to CIO or CTO. Depends on the size of the organization, there can be Chief Cloud architect also, where all the Cloud architects report to this position.

https://vskumar.blog/2019/02/14/what-will-be-the-size-of-cloud-market-in-it-by-2022/

Note:

The DevOps Architect need not put his fingers into low level command scripts. It is the responsibility of the DevOps Engineers.

Hope this blog clarifies for many people.

AWS-SAA-Course

 

 

 

 

 

Also read the below blog on how the Costly Cloud Defects are getting created:

https://vskumar.blog/2019/10/14/how-the-cloud-professionals-can-create-the-costly-defects-and-the-reasons/

DevOps Practices coaching

Coaching on DevOps Practices —–>

This coaching is meant for DevOps Managers and above positions only…

  1. Please walk-through the below chart for your DevOps practices implementation. These are nowhere connected with any specific DevOps tools. Just practices implementation only to show your velocity in DevOps complianced projects execution.  
  2. These are the best practices used by the DevOps successful implementation organizations.
  3. Who need to learn these?: If you are already working as DevOps professional, [Ex: DevOps engineer, Practitioner, Architect, Practice head, Related to DevOps implementation, etc.] and your organization is demanding/targeted to demonstrate its [DevOps implementation] velocity then you need to accelerate your speed in catching up the knowledge on several areas for  continuous improvements.
  4. Note; you also need to apply continuous learning or seek coaching to speedup your productivity through experienced professionals.

Visit for free concepts learning:

To join DevOps Practices group visit  [CONDITIONS APPLY]:

https://www.facebook.com/groups/1911594275816833/about/

To join Cloud Practices group visit [CONDITIONS APPLY]:

https://www.facebook.com/groups/585147288612549/about/

DevOps Patterns

Note:

Please note this course doesn’t contain Tools. Only Practices.

There is a separate topic “DevOps Automation”, you need to attend it.

If you are qualified you can join the below group also.

https://vskumar.blog/2018/10/17/join-devops-practices-group-on-fb/

If you are  new for DevOps, visit:

https://vskumar.blog/2017/10/22/why-the-devops-practice-is-mandatory-for-an-it-employee/

You can also visit:

https://vskumar.blog/2019/07/24/devops-advanced-devops-practices-processes-1/

Advt-course3rd page.png
Folks! Greetings!

Are you interested to transform into new technology ?

An IT employee need to learn DevOps and also one cloud technology practice which is mandatory to understand the current DevOps work culture to get accommodated into a project.
Visit for my course exercises/sample videos/blogs on youtube channel and the blog site mentioned in VCard.
I get many new users regularly  to use these content from different countries.
That itself denotes they are highly competitive techie stuff.
During the course you will be given cloud infra machine(s) [they will be your property] into your laptop for future self practice for interviews, R&D, etc.
The critical  topics will have supporting blogs/videos!! along with the pdf material.
In a corporate style training cos you will be given access [upto certain period] only to their cloud setup.
These are the USPs can be compared with other courses!
Please come with joining confirmation/determination.
For classroom sessions it will be in Vijayanagar, Bangalore, India.
Both online and classroom are available for weekend [global flexible timings] and weekdays to facilitate employees.
Corporate companies are welcome to avail it to save cost of your suppliers!!
You can join from any country for online course.
For contacts please go through vCard. Please send E-mail on your willingness.
Looking forward for your learning call/e-mail!
Look into this video also:
Visit For Aws Lab demo:
WATCH STUDENT FEEDBACK ON AWS:

 

 

Visit some more videos:
Visit:

1. AWS:How to create and activate a new account in AWS ?

AWS Account-creation scrn

How to create and activate a new account in AWS ?:

In this blog, you will see the required steps for creating and activating your new AWS account. Once have the activated account, you can start your other lab practices as I discuss in the class timely.

The following are the main 4 steps process we need to follow:

STEP1: Creating your account. It consists of 2 steps: a) Providing a valid e-mail address and choosing a password. b) Providing your contact information and setting your preferences.

STEP2: Add a payment method Please note; you need to have a valid CC to give its details. Amazon verifies its transaction also with a tiny charge and with a credit back. If by mistaken given wrong data please note; your account registration process will not be activated. You will be intimated by mail. This way Amazon is authenticating/authorizing us for AWS usage.

STEP3: Verify your phone number. You need to Provide a phone number where you can be reached in next few minutes, while creating your account.

STEP4: Choose the AWS Support plans. Time to time the AWS plans will be published. You need to choose the plan from the currently available plans for your needs. The relevant URL is given in the detailed steps section in this blog.

As a consolidated process, we can understand from the below flow chart. Which is from the collection of AWS process charts.

AWS Account-creation flowchart

Note:

I am not copying the screens due to privacy.

Detailed steps

STEP1: Detailed steps for Creating your account.

a). You need to go to Amazon Web Services home page URL: https://aws.amazon.com/

b). Now, Choose Sign Up. Click on Create an AWS account. You can see new page with Create an AWS account. You need to enter the required details. E-mail id, Pwd, AWS Account name [you can give any name for this]. And choose continue to go to next page. Please note; The above steps are valid for the new users of AWS. If you enter your email address entered incorrectly, you might not be able to access your account or change your password in the future. So you need to be careful on your data entry part. Let us assume; if you’ve signed in to AWS recently, it might say Sign In to the Console. So you need to login into your existing Account.

c). Now in the current page, choose Professional or personal. These two areas will give equal services. Depends on your need You can choose one of the options.

d). From the above options choosed, type the requested company or personal information entries. Note; At this point, You need to go through the AWS Customer Agreement to know their policies and procedures to follow while operating.

e). Finally, you choose Create Account and Continue options in the bottom.

f). Please note; at this point you will receive an e-mail to confirm that your account is created. Now, you can sign in to your new account using the valid email address and valid password you have supplied earlier.

Please note; we have done the Step1 only, the activation process is not yet completed to use the AWS services. Still we need to follow 3 more steps.

STEP2: Add a payment method- Detailed steps:

At this point; On the Payment Information page,

a) Choose the payment method as per the payment gateway standards which is displayed.

b) Type the requested information associated with your payment method. Please make sure the address for your payment method is the same as the address you provided for your account. Note; If your billing address is different; then choose Use a new address, type the billing address for your payment method.

c) Now, choose Secure Submit.

STEP3: Verify your phone number.

Please keep a valid and handy phone number at this point.

a) On this Phone Verification page, type a phone number where can use to accept incoming phone calls.

b) Enter the code displayed in the captcha. When you’re ready to receive a call, choose Call me now option.

c) In a few moments, an automated system will call you to your given phone number. Even it might have SMS feature also, if you are outside North America region.

d) Type the provided PIN on your phone’s keypad of the AWS screen. e) After the process is complete, choose Continue.

STEP4: Choose the AWS Support plans.

a) At this point please visit the below URL: https://aws.amazon.com/premiumsupport/features/

You can select the AWS support plans from the given list.

b) After your selection of a Support plan, a confirmation page denotes that your account is being activated.

c) Please note; Accounts are usually activated within a few minutes, but the process might take up to 24 hours. This process includes the validation of Bank/CC account given there.

d) Hence keep looking for a mail on this subject from Amazon to start your AWS services usage.

Assuming everything went well, and your AWS account is activated now.  Congratulations!

We can look into next lab with reference to the class session.

2. AWS: WordPress[WP] infrastructure creation using a free tier account

https://wordpress.com/post/vskumar.blog/2884

 

If you are interested to learn Virtualization with Vagrant visit:

1. Vagrant/Virtual Box:How to create Virtual Machine[VM] on Windows 10?:

 

Note:

If you are not a student of my class, and looking for it please contact me by mail with your LinkedIn identity. And send a connection request with a message on your need. You can use the below contacts. Please note; I teach globally.

 

Vcard-Shanthi Kumar V-v3

27.DevOps:Working with SSH for Ansible usage

ssh

Working with SSH for Ansible usage:
With reference to my blog on Ansible installation on Ubuntu VM,  https://vskumar.blog/2018/05/08/23-devops-how-to-install-ansible-on-ubuntu-linux-vm/

in this blog, I have demonstrated on playing around with ssh among three
ubuntu Vmware Virtual machines.

To use Ansible exercises we need to follow the below pre-requisites with ssh operations.

Pre-requisites for Ansible usage:
https://help.ubuntu.com/community/SSH/OpenSSH/Keys

SSH Keys for Ansible VMs usage:
Before using Ansible we need to make sure the SSH is installed in the
VMs.
I would like to give the steps for this setup as below:

Pre-requisite Step1:
Install OpenSSH on Ubuntu.
Update the package index using the following command:
sudo apt-get update

To install the OpenSSH server application as well as the other related
packages use the command below:
sudo apt-get install openssh-server

Further, you can install the OpenSSH client application using
the following command:
sudo apt-get install openssh-client

Pre-requisite Step2:
Configure OpenSSH on Ubuntu
Before making any changes in OpenSSH configuration,
we need to know how to manage the OpenSSH service on Ubuntu VMs.

How to check ssh version?:
use the command; ssh -V

i) To start the service we can use the following command:
sudo systemctl start sshd.service

ii) To stop the service we can use:
sudo systemctl stop sshd.service

iii) To restart the service we can use:
sudo systemctl restart sshd.service

iv) To check the status of the service we can use:
sudo systemctl status sshd.service

v) If we want to enable the service on system boot we can use:
sudo systemctl enable sshd.service

vi) If we want to disable the service on system boot we can use:
sudo systemctl disable sshd.service

vii) The configuration file for the OpenSSH server application
is in the folder:/etc/ssh/sshd_config
We need to update the default port in this file.
We need to make sure to create a backup of the original configuration before
making any changes:
sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.orig

We can edit the file by using a text editor of our choice either vi or vim, etc..
The first thing we must do is to change the default SSH listening port.
Open the file and locate the line that specifies the listening port:
Port 22
Change it to your desired port number. Ex: Port 1990

Save the file and close it.
Then restart the service for the changes to take effect.

Note:
After making any changes in the OpenSSH configuration you need to restart the service
for the changes to take effect.

Pre-requisite Step3: Create an SSH key pair
Please note, during Ansible exercise or other DevOps tools, we need to connect to other VMs using SSH keys.

Let us note; the Key-based authentication uses two keys, one “public” key that anyone is allowed
to see.
And another “private” key that only the owner is allowed to see.
To securely communicate using key-based authentication, one needs to create a key pair,
securely store the private key on the computer which we want to log in from [Source machine],
and store the public key on the other Virtual Machine[Target machine] one wants to log in to.
Using key based logins with ssh is generally considered more secure than using plain password logins.

Now, let us see these steps:
1. Generating RSA Keys:
Our first step involves creating a set of RSA keys for use in authentication.
This should be done on the client.
To create our public and private SSH keys we need to use the below commands:
mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa

We will be prompted for a location to save the keys, and a passphrase for the keys.
This passphrase will protect our private key while it’s stored on the hard drive:

=== Sample Output ====>
Generating public/private rsa key pair.
Enter file in which to save the key (/home/b/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/b/.ssh/id_rsa.
Your public key has been saved in /home/b/.ssh/id_rsa.pub.
======================>
Note; An SSH key passphrase is a secondary form of security.
You need to remember it while logging the remote machine.
Now, our public key is now available as .ssh/id_rsa.pub in the home directory.

The file name and pwd can be given when you follow rigid security procedures as per your project setup. Here if you avoid in giving name/pwd, it makes us easy to copy the key file to target machine.

2. Transfer Client Key to Host:
The key we need to transfer to the host is the public one.
If we can log in to a computer over SSH using a password,
we can transfer our RSA key by doing the following from our own computer:
Command format:
====>
ssh-copy-id <username>@<host>
====>
Note: The <username> and <host> should be replaced by our username
and the name of the computer we’re transferring our key to.

TIP on Port# usage:
We cannot specify a port other than the standard port 22 [unless we changed it to
another port# in the target VM]. we can work around this by issuing the
command like this: ssh-copy-id “<username>@<host> -p <port_nr>”.
If we are using the standard port 22, we can ignore this tip.

We can make sure this worked by doing the below command test:
ssh <username>@<host>

We should be prompted for the passphrase for our key:
Enter passphrase for key ‘/home/<user>/.ssh/id_rsa’:
Enter your passphrase, and provided host is configured to allow key-based logins,
we should then be logged in as usual.

 

How to remove the existing SSH from Ubuntu ?
If we have already ssh we can use the below steps to remove and
get the latest setup.

Step1: Stop SSH service before uninstalling it.
service ssh stop

Step2: Now, we need to Uninstall and remove the ssh package from the machine by using the below
apt-get command.

apt-get purge openssh-server

Now you can check its status using ssh -VM
If it is not there you should not get the version.

Please note my VMs Ips,where i will apply some exercises timely:

IP of Ans-ControlMachine:
192.168.116.132

IP of VM1:
192.168.116.134

IP of VM2:
192.168.116.135

IP of VM3:
192.168.116.133

The machine names are prompted in CLI.
I am using these four Virtual machines on Vmware environment with player as well as Workstation.

I have played around with SSH among these machines.
I have copied most of the screen outputs in this content.

Removing SSH from one Virtual machine for installating procedure testing:
I have preloaded SSH earlier.
I am purging SSH in one Virtual machine to demonstrate the exercise.
And below I have copied the screen outputs also.

==== Screen outputs for Ans-ControlMachine =====>
=== Removing SSH from Ans-ControlMachine=========>
vskumar@ubuntu:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$ service ssh stop
Failed to stop ssh.service: Unit ssh.service not loaded.
vskumar@ubuntu:~$ service ssh status
● ssh.service
Loaded: not-found (Reason: No such file or directory)
Active: inactive (dead)
vskumar@ubuntu:~$
vskumar@ubuntu:~$ apt-get -purge openssh-server
E: Command line option ‘p’ [from -purge] is not understood in combination with the other options.
vskumar@ubuntu:~$ apt-get purge remove openssh-server
E: Could not open lock file /var/lib/dpkg/lock – open (13: Permission denied)
E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?
vskumar@ubuntu:~$ sudo apt-get purge remove openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
E: Unable to locate package remove
vskumar@ubuntu:~$ sudo apt-get purge openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
Package ‘openssh-server’ is not installed, so not removed
0 upgraded, 0 newly installed, 0 to remove and 432 not upgraded.

vskumar@ubuntu:~$ sudo apt-get purge openssh-client
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages will be REMOVED:
openssh-client* snapd* ubuntu-core-launcher*
0 upgraded, 0 newly installed, 3 to remove and 429 not upgraded.
After this operation, 61.7 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database … 176110 files and directories currently installed.)
Removing ubuntu-core-launcher (2.25) …
Removing snapd (2.25) …
Warning: Stopping snapd.service, but it can still be activated by:
snapd.socket
Purging configuration files for snapd (2.25) …
Final directory cleanup
Discarding preserved snap namespaces
umount: /run/snapd/ns/*.mnt: mountpoint not found
umount: /run/snapd/ns/: mountpoint not found
Removing extra snap-confine apparmor rules
Removing snapd state
Removing openssh-client (1:7.2p2-4ubuntu2.2) …
Purging configuration files for openssh-client (1:7.2p2-4ubuntu2.2) …
Processing triggers for man-db (2.7.5-1) …

vskumar@ubuntu:~$
s for man-db (2.7.5-1) …
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ssh -V
bash: /usr/bin/ssh: No such file or directory
vskumar@ubuntu:~$
== So we have completely removed the SSH ====>
=== from Ans-ControlMachine=========>

Installing SSH into Ans-ControlMachine:

Now, let me install the SSH server and client also.
Step1:
Let update the packages.
sudo apt-get update

== Output =======>
vskumar@ubuntu:~$ sudo apt-get update

Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [107 kB]
Hit:2 http://us.archive.ubuntu.com/ubuntu xenial InRelease
Get:3 http://us.archive.ubuntu.com/ubuntu xenial-updates InRelease [109 kB]
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Get:5 http://security.ubuntu.com/ubuntu xenial-security/main amd64 DEP-11 Metadata [67.7 kB]
Get:6 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 DEP-11 Metadata [319 kB]
Get:7 http://security.ubuntu.com/ubuntu xenial-security/main DEP-11 64×64 Icons [72.6 kB]
Get:8 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 DEP-11 Metadata [107 kB]
Get:9 http://security.ubuntu.com/ubuntu xenial-security/universe DEP-11 64×64 Icons [147 kB]
Get:10 http://us.archive.ubuntu.com/ubuntu xenial-updates/main DEP-11 64×64 Icons [226 kB]
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Get:12 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe DEP-11 64×64 Icons [331 kB]
Get:13 http://us.archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 DEP-11 Metadata [5,964 B]
Get:14 http://us.archive.ubuntu.com/ubuntu xenial-backports/main amd64 DEP-11 Metadata [3,324 B]
Get:15 http://us.archive.ubuntu.com/ubuntu xenial-backports/universe amd64 DEP-11 Metadata [5,088 B]
Fetched 1,853 kB in 11s (168 kB/s)
Reading package lists… Done
vskumar@ubuntu:~$
============>

Step2: Installing server
Now, we will use the below command to install ssh srver:
sudo apt-get install openssh-server

==== Screen output ======>
vskumar@ubuntu:~$ sudo apt-get install openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
ncurses-term openssh-client openssh-sftp-server ssh-import-id
Suggested packages:
ssh-askpass libpam-ssh keychain monkeysphere rssh molly-guard
The following NEW packages will be installed:
ncurses-term openssh-client openssh-server openssh-sftp-server ssh-import-id
0 upgraded, 5 newly installed, 0 to remove and 429 not upgraded.
Need to get 1,222 kB of archives.
After this operation, 8,917 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-client amd64 1:7.2p2-4ubuntu2.4 [589 kB]
Get:2 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ncurses-term all 6.0+20160213-1ubuntu1 [249 kB]
Get:3 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-sftp-server amd64 1:7.2p2-4ubuntu2.4 [38.7 kB]
Get:4 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-server amd64 1:7.2p2-4ubuntu2.4 [335 kB]
Get:5 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ssh-import-id all 5.5-0ubuntu1 [10.2 kB]
Fetched 1,222 kB in 7s (162 kB/s)
Preconfiguring packages …
Selecting previously unselected package openssh-client.
(Reading database … 176023 files and directories currently installed.)
Preparing to unpack …/openssh-client_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-client (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ncurses-term.
Preparing to unpack …/ncurses-term_6.0+20160213-1ubuntu1_all.deb …
Unpacking ncurses-term (6.0+20160213-1ubuntu1) …
Selecting previously unselected package openssh-sftp-server.
Preparing to unpack …/openssh-sftp-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package openssh-server.
Preparing to unpack …/openssh-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ssh-import-id.
Preparing to unpack …/ssh-import-id_5.5-0ubuntu1_all.deb …
Unpacking ssh-import-id (5.5-0ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
Processing triggers for ufw (0.35-0ubuntu2) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Setting up openssh-client (1:7.2p2-4ubuntu2.4) …
Setting up ncurses-term (6.0+20160213-1ubuntu1) …
Setting up openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Setting up openssh-server (1:7.2p2-4ubuntu2.4) …
Creating SSH2 RSA key; this may take some time …
2048 SHA256:3yMAIuH8WhE4tf0kwEqrBHo7gxj3nYq/RTXhYMrpz/s root@ubuntu (RSA)
Creating SSH2 DSA key; this may take some time …
1024 SHA256:HoY3UATMD48l8tOWSWQcJWtwK+s98j7WpD7WGEPsbVo root@ubuntu (DSA)
Creating SSH2 ECDSA key; this may take some time …
256 SHA256:sIDDAzkiGiTCzpGHOTEU3QbG/oNn4DNvXxHtm7kzAZ4 root@ubuntu (ECDSA)
Creating SSH2 ED25519 key; this may take some time …
256 SHA256:hGlI7mLNIGbU2bs/igS1YZrNwxxCvFpszZxOCAOozGk root@ubuntu (ED25519)
Setting up ssh-import-id (5.5-0ubuntu1) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Processing triggers for ufw (0.35-0ubuntu2) …
vskumar@ubuntu:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.4, OpenSSL 1.0.2g 1 Mar 2016
vskumar@ubuntu:~$
=======================>

Step3: install client
We can try to install the OpenSSH client application using
the following command:
sudo apt-get install openssh-client

==== Screen output =====================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt-get install openssh-client
Reading package lists… Done
Building dependency tree
Reading state information… Done
openssh-client is already the newest version (1:7.2p2-4ubuntu2.4).
openssh-client set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 429 not upgraded.
vskumar@ubuntu:~$
=== It is installed along with server ====>

Step4:
Now, let us check the status:

=== Status of SSH server ===>
vskumar@ubuntu:~$ sudo systemctl status sshd.service
● ssh.service – OpenBSD Secure Shell server
Loaded: loaded (/lib/systemd/system/ssh.service; enabled; vendor preset: enab
Active: active (running) since Sat 2018-05-26 05:21:18 PDT; 6min ago
Main PID: 4645 (sshd)
CGroup: /system.slice/ssh.service
└─4645 /usr/sbin/sshd -D

May 26 05:21:17 ubuntu systemd[1]: Starting OpenBSD Secure Shell server…
May 26 05:21:17 ubuntu sshd[4645]: Server listening on 0.0.0.0 port 22.
May 26 05:21:17 ubuntu sshd[4645]: Server listening on :: port 22.
May 26 05:21:18 ubuntu systemd[1]: Started OpenBSD Secure Shell server.
lines 1-11/11 (END)
vskumar@ubuntu:~$
============================>

Generating RSA Keys:
Step1:
To create our public and private SSH keys we need to use the below commands:
mkdir ~/.ssh
chmod 700 ~/.ssh
ssh-keygen -t rsa

=== Screen output ===>
vskumar@ubuntu:~$ ls
Desktop Downloads Music Public Videos
Documents examples.desktop Pictures Templates
vskumar@ubuntu:~$ ls -la
total 116
drwxr-xr-x 17 vskumar vskumar 4096 May 26 05:30 .
drwxr-xr-x 3 root root 4096 Nov 22 2017 ..
-rw——- 1 vskumar vskumar 524 Mar 6 18:06 .bash_history
-rw-r–r– 1 vskumar vskumar 220 Nov 22 2017 .bash_logout
-rw-r–r– 1 vskumar vskumar 3771 Nov 22 2017 .bashrc
drwx—— 13 vskumar vskumar 4096 May 26 04:45 .cache
drwx—— 14 vskumar vskumar 4096 Nov 22 2017 .config
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Desktop
-rw-r–r– 1 vskumar vskumar 25 Nov 22 2017 .dmrc
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Documents
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Downloads
-rw-r–r– 1 vskumar vskumar 8980 Nov 22 2017 examples.desktop
drwx—— 2 vskumar vskumar 4096 Dec 22 21:36 .gconf
drwx—— 3 vskumar vskumar 4096 May 26 04:42 .gnupg
-rw——- 1 vskumar vskumar 3498 May 26 04:42 .ICEauthority
drwx—— 3 vskumar vskumar 4096 Nov 22 2017 .local
drwx—— 4 vskumar vskumar 4096 Nov 22 2017 .mozilla
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Music
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Pictures
-rw-r–r– 1 vskumar vskumar 655 Nov 22 2017 .profile
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Public
drwxrwxr-x 2 vskumar vskumar 4096 May 26 05:30 .ssh
-rw-r–r– 1 vskumar vskumar 0 Nov 22 2017 .sudo_as_admin_successful
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Templates
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 2017 Videos
-rw——- 1 vskumar vskumar 51 May 26 04:42 .Xauthority
-rw——- 1 vskumar vskumar 82 May 26 04:42 .xsession-errors
-rw——- 1 vskumar vskumar 82 May 26 03:11 .xsession-errors.old
vskumar@ubuntu:~$
vskumar@ubuntu:~$ chmod 700 ~/.ssh
I copied on the below line:
drwx—— 2 vskumar vskumar 4096 May 26 05:30 .ssh
The rights are changed.
======================>

=========================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/vskumar/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/vskumar/.ssh/id_rsa.
Your public key has been saved in /home/vskumar/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:jLVDx+RqfC+3lo3qcajm+gcHO+44+h/cfTDDLHtsEAg vskumar@ubuntu
The key’s randomart image is:
+—[RSA 2048]—-+
| E . |
| . = |
| + = |
| *.+ + |
| . So+ * |
| o++.O + |
| .o+* O+. |
| ..oo.B+o. |
| .o+O*ooo. |
+—-[SHA256]—–+
vskumar@ubuntu:~$
=== I have given the pwd for passphrase ====>

Step2: Transfer Client Key to Host
ssh-copy-id <username>@<host>
I will try with VM1.
==== Copting ssh id to VM1 ====>
== From Ans-ControlMachine ====>
vskumar@ubuntu:~/.ssh$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~/.ssh$ ls
id_rsa id_rsa.pub known_hosts
vskumar@ubuntu:~/.ssh$ ssh ssh-copy-id vskumar@192.168.116.134
ssh: Could not resolve hostname ssh-copy-id: Name or service not known
vskumar@ubuntu:~/.ssh$ sudo ssh-copy-id vskumar@192.168.116.134
[sudo] password for vskumar:
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: “/home/vskumar/.ssh/id_rsa.pub”
The authenticity of host ‘192.168.116.134 (192.168.116.134)’ can’t be established.
ECDSA key fingerprint is SHA256:ZPPT6yQv8nAC1A6cDkeIssDYiim81f4/88I+NNVm1Iw.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed — if you are prompted now it is to install the new keys
vskumar@192.168.116.134’s password:

Number of key(s) added: 1

Now try logging into the machine, with: “ssh ‘vskumar@192.168.116.134′”
and check to make sure that only the key(s) you wanted were added.

vskumar@ubuntu:~/.ssh$

==== Copied ssh key to VM1 ===>

======From VM1 =====>
vskumar@VM1:~$
vskumar@VM1:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM1:~$ service ssh stop
Failed to stop ssh.service: Unit ssh.service not loaded.
vskumar@VM1:~$ apt-get -purge openssh-server
E: Command line option ‘p’ [from -purge] is not understood in combination with the other options.
vskumar@VM1:~$ sudo apt-get -purge openssh-server
[sudo] password for vskumar:
E: Command line option ‘p’ [from -purge] is not understood in combination with the other options.
vskumar@VM1:~$ sudo apt-get purge openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
Package ‘openssh-server’ is not installed, so not removed
0 upgraded, 0 newly installed, 0 to remove and 432 not upgraded.
vskumar@VM1:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM1:~$ sudo apt-get purge openssh-client
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages will be REMOVED:
openssh-client* snapd* ubuntu-core-launcher*
0 upgraded, 0 newly installed, 3 to remove and 429 not upgraded.
After this operation, 61.7 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database … 176110 files and directories currently installed.)
Removing ubuntu-core-launcher (2.25) …
Removing snapd (2.25) …
Warning: Stopping snapd.service, but it can still be activated by:
snapd.socket
Purging configuration files for snapd (2.25) …
Final directory cleanup
Discarding preserved snap namespaces
umount: /run/snapd/ns/*.mnt: mountpoint not found
umount: /run/snapd/ns/: mountpoint not found
Removing extra snap-confine apparmor rules
Removing snapd state
Removing openssh-client (1:7.2p2-4ubuntu2.2) …
Purging configuration files for openssh-client (1:7.2p2-4ubuntu2.2) …
Processing triggers for man-db (2.7.5-1) …
vskumar@VM1:~$
vskumar@VM1:~$ ssh -V
bash: /usr/bin/ssh: No such file or directory
vskumar@VM1:~$

vskumar@VM1:~$ sudo apt-get update
0% [Working]
Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [107 kB]
Hit:2 http://us.archive.ubuntu.com/ubuntu xenial InRelease
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Get:5 http://security.ubuntu.com/ubuntu xenial-security/main amd64 DEP-11 Metadata [67.7 kB]
Get:6 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [783 kB]
Get:7 http://security.ubuntu.com/ubuntu xenial-security/main DEP-11 64×64 Icons [72.6 kB]
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Get:10 http://us.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages [718 kB]
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Get:13 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [631 kB]
Get:14 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe i386 Packages [577 kB]
Get:15 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 DEP-11 Metadata [246 kB]
Get:16 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe DEP-11 64×64 Icons [331 kB]
Get:17 http://us.archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 DEP-11 Metadata [5,964 B]
Get:18 http://us.archive.ubuntu.com/ubuntu xenial-backports/main amd64 DEP-11 Metadata [3,324 B]
Get:19 http://us.archive.ubuntu.com/ubuntu xenial-backports/universe amd64 DEP-11 Metadata [5,088 B]
Fetched 4,562 kB in 24s (187 kB/s)
Reading package lists… Done
vskumar@VM1:~$

vskumar@VM1:~$
vskumar@VM1:~$ sudo apt-get install openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
ncurses-term openssh-client openssh-sftp-server ssh-import-id
Suggested packages:
ssh-askpass libpam-ssh keychain monkeysphere rssh molly-guard
The following NEW packages will be installed:
ncurses-term openssh-client openssh-server openssh-sftp-server ssh-import-id
0 upgraded, 5 newly installed, 0 to remove and 429 not upgraded.
Need to get 1,222 kB of archives.
After this operation, 8,917 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-client amd64 1:7.2p2-4ubuntu2.4 [589 kB]
Get:2 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ncurses-term all 6.0+20160213-1ubuntu1 [249 kB]
Get:3 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-sftp-server amd64 1:7.2p2-4ubuntu2.4 [38.7 kB]
Get:4 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-server amd64 1:7.2p2-4ubuntu2.4 [335 kB]
Get:5 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ssh-import-id all 5.5-0ubuntu1 [10.2 kB]
Fetched 1,222 kB in 7s (160 kB/s)
Preconfiguring packages …
Selecting previously unselected package openssh-client.
(Reading database … 176023 files and directories currently installed.)
Preparing to unpack …/openssh-client_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-client (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ncurses-term.
Preparing to unpack …/ncurses-term_6.0+20160213-1ubuntu1_all.deb …
Unpacking ncurses-term (6.0+20160213-1ubuntu1) …
Selecting previously unselected package openssh-sftp-server.
Preparing to unpack …/openssh-sftp-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package openssh-server.
Preparing to unpack …/openssh-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ssh-import-id.
Preparing to unpack …/ssh-import-id_5.5-0ubuntu1_all.deb …
Unpacking ssh-import-id (5.5-0ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
Processing triggers for ufw (0.35-0ubuntu2) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Setting up openssh-client (1:7.2p2-4ubuntu2.4) …
Setting up ncurses-term (6.0+20160213-1ubuntu1) …
Setting up openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Setting up openssh-server (1:7.2p2-4ubuntu2.4) …
Creating SSH2 RSA key; this may take some time …
2048 SHA256:4efQhtH82rrRfTvvYxt3Wu7lJg0HJcW66yEi6WaTN+c root@VM1 (RSA)
Creating SSH2 DSA key; this may take some time …
1024 SHA256:fGZ3vX279MRTXsRhzYyHSPIwVv7ge2/WRQmh+SHlIZo root@VM1 (DSA)
Creating SSH2 ECDSA key; this may take some time …
256 SHA256:ZPPT6yQv8nAC1A6cDkeIssDYiim81f4/88I+NNVm1Iw root@VM1 (ECDSA)
Creating SSH2 ED25519 key; this may take some time …
256 SHA256:5rZGM1Q0vbVD82kcvKS4NdtzCGgDIaiEjL+C01+iJgU root@VM1 (ED25519)
Setting up ssh-import-id (5.5-0ubuntu1) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Processing triggers for ufw (0.35-0ubuntu2) …
vskumar@VM1:~$
vskumar@VM1:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.4, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM1:~$

==========================>

 

===Connecting to >
vskumar@VM1:~$ ssh vskumar@Ans-ControlMachine
ssh: Could not resolve hostname ans-controlmachine: Name or service not known
vskumar@VM1:~$ ssh vskumar@192.168.116.132
The authenticity of host ‘192.168.116.132 (192.168.116.132)’ can’t be established.
ECDSA key fingerprint is SHA256:sIDDAzkiGiTCzpGHOTEU3QbG/oNn4DNvXxHtm7kzAZ4.
Are you sure you want to continue connecting (yes/no)? y
Please type ‘yes’ or ‘no’: yes
Warning: Permanently added ‘192.168.116.132’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

 

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

vskumar@ubuntu:~$

vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM1:~$ cat /etc/hostname
VM1
vskumar@VM1:~$
==== Connected from VM1 to ======>
==== Ans-ControlMachine and exit ======>

I am connecting to VM1 from Ans-ControlMachine through ssh.

== Connecting to VM1 from ==>
====Ans-ControlMachine =====>
vskumar@ubuntu:~/.ssh$ ssh vskumar@192.168.116.134
The authenticity of host ‘192.168.116.134 (192.168.116.134)’ can’t be established.
ECDSA key fingerprint is SHA256:ZPPT6yQv8nAC1A6cDkeIssDYiim81f4/88I+NNVm1Iw.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.134’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.134’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

 

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

vskumar@VM1:~$ cat /etc/hostname
VM1
vskumar@VM1:~$
vskumar@VM1:~$
vskumar@VM1:~$ exit
logout
Connection to 192.168.116.134 closed.
vskumar@ubuntu:~/.ssh$
vskumar@ubuntu:~/.ssh$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~/.ssh$
======= Exit from VM1 And back ====>
==== to Ans-ControlMachine ====>

 

=== Connecting from VM1 to VM2 ===>
== Connecting in the same SSH ====>
== From VM1 to Ans-ControlMachine ====>
== You can play around with ssh ====>
== Across VMs by using IPs ========>
vskumar@VM2:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM2:~$ sudo ssh vskumar@VM1
[sudo] password for vskumar:
ssh: Could not resolve hostname vm1: Name or service not known
vskumar@VM2:~$ sudo ssh vskumar@192.168.116.134
The authenticity of host ‘192.168.116.134 (192.168.116.134)’ can’t be established.
ECDSA key fingerprint is SHA256:ZPPT6yQv8nAC1A6cDkeIssDYiim81f4/88I+NNVm1Iw.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.134’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.134’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 06:00:10 2018 from 192.168.116.132
vskumar@VM1:~$ cat /etc/hostname
VM1
vskumar@VM1:~$ ssh vskumar@192.168.116.132
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 05:55:36 2018 from 192.168.116.134
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM1:~$

vskumar@VM1:~$ exit
logout
Connection to 192.168.116.134 closed.
vskumar@VM2:~$ cat /etc/hostname
VM2
vskumar@VM2:~$
== We have played around 3 VMs ===>
=== With SSH =====================>

 

=== Connecting from VM2 ===>
==== tO Ans-ControlMachine===>
vskumar@VM2:~$ ssh vskumar@192.168.116.132
The authenticity of host ‘192.168.116.132 (192.168.116.132)’ can’t be established.
ECDSA key fingerprint is SHA256:sIDDAzkiGiTCzpGHOTEU3QbG/oNn4DNvXxHtm7kzAZ4.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.132’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 06:05:18 2018 from 192.168.116.134
vskumar@ubuntu:~$
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM2:~$
==== Conneted from VM2 ==>

=== Removing ssh from VM2 ====>
== To have clean files ========>
vskumar@VM2:~$ sudo apt-get purge openssh-client
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages will be REMOVED:
openssh-client* snapd* ubuntu-core-launcher*
0 upgraded, 0 newly installed, 3 to remove and 429 not upgraded.
After this operation, 61.7 MB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database … 176110 files and directories currently installed.)
Removing ubuntu-core-launcher (2.25) …
Removing snapd (2.25) …
Warning: Stopping snapd.service, but it can still be activated by:
snapd.socket
Purging configuration files for snapd (2.25) …
Final directory cleanup
Discarding preserved snap namespaces
umount: /run/snapd/ns/*.mnt: mountpoint not found
umount: /run/snapd/ns/: mountpoint not found
Removing extra snap-confine apparmor rules
Removing snapd state
Removing openssh-client (1:7.2p2-4ubuntu2.2) …
Purging configuration files for openssh-client (1:7.2p2-4ubuntu2.2) …
Processing triggers for man-db (2.7.5-1) …
vskumar@VM2:~$
vskumar@VM2:~$ ssh -V
bash: /usr/bin/ssh: No such file or directory
vskumar@VM2:~$
===== SSH is removed in VM2 ====>

=== Installing ssh in VM2 ====>
vskumar@VM2:~$ sudo apt-get install openssh-server
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
ncurses-term openssh-client openssh-sftp-server ssh-import-id
Suggested packages:
ssh-askpass libpam-ssh keychain monkeysphere rssh molly-guard
The following NEW packages will be installed:
ncurses-term openssh-client openssh-server openssh-sftp-server ssh-import-id
0 upgraded, 5 newly installed, 0 to remove and 429 not upgraded.
Need to get 633 kB/1,222 kB of archives.
After this operation, 8,917 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ncurses-term all 6.0+20160213-1ubuntu1 [249 kB]
Get:2 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-sftp-server amd64 1:7.2p2-4ubuntu2.4 [38.7 kB]
Get:3 http://us.archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssh-server amd64 1:7.2p2-4ubuntu2.4 [335 kB]
Get:4 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 ssh-import-id all 5.5-0ubuntu1 [10.2 kB]
Fetched 633 kB in 34s (18.5 kB/s)
Preconfiguring packages …
Selecting previously unselected package openssh-client.
(Reading database … 176023 files and directories currently installed.)
Preparing to unpack …/openssh-client_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-client (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ncurses-term.
Preparing to unpack …/ncurses-term_6.0+20160213-1ubuntu1_all.deb …
Unpacking ncurses-term (6.0+20160213-1ubuntu1) …
Selecting previously unselected package openssh-sftp-server.
Preparing to unpack …/openssh-sftp-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package openssh-server.
Preparing to unpack …/openssh-server_1%3a7.2p2-4ubuntu2.4_amd64.deb …
Unpacking openssh-server (1:7.2p2-4ubuntu2.4) …
Selecting previously unselected package ssh-import-id.
Preparing to unpack …/ssh-import-id_5.5-0ubuntu1_all.deb …
Unpacking ssh-import-id (5.5-0ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
Processing triggers for ufw (0.35-0ubuntu2) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Setting up openssh-client (1:7.2p2-4ubuntu2.4) …
Setting up ncurses-term (6.0+20160213-1ubuntu1) …
Setting up openssh-sftp-server (1:7.2p2-4ubuntu2.4) …
Setting up openssh-server (1:7.2p2-4ubuntu2.4) …
Creating SSH2 RSA key; this may take some time …
2048 SHA256:JzaY4P+pXshET4rzo/+nkNxGxWe9Hl2Vljd5OV9upko root@VM2 (RSA)
Creating SSH2 DSA key; this may take some time …
1024 SHA256:M49R3FKLVlxGFRw8Caf+s1ktna9h3Ak5Ls93+TyBrac root@VM2 (DSA)
Creating SSH2 ECDSA key; this may take some time …
256 SHA256:/HtM2RyrOSeFO01WW3d1S5fcB9mBM7MApniY54Nq4k4 root@VM2 (ECDSA)
Creating SSH2 ED25519 key; this may take some time …
256 SHA256:lbmYMsRLrCR23898dlX4TidNFYkasm3w/lpyl0oZXfg root@VM2 (ED25519)
Setting up ssh-import-id (5.5-0ubuntu1) …
Processing triggers for systemd (229-4ubuntu19) …
Processing triggers for ureadahead (0.100.0-19) …
Processing triggers for ufw (0.35-0ubuntu2) …
vskumar@VM2:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.4, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM2:~$
== Now VM2 has the complete ssh =====>

=== Now let me connect to ===>
====Ans-ControlMachine ======>
== From VM2 =================>

vskumar@VM2:~$ sudo ssh vskumar@192.168.116.132
The authenticity of host ‘192.168.116.132 (192.168.116.132)’ can’t be established.
ECDSA key fingerprint is SHA256:sIDDAzkiGiTCzpGHOTEU3QbG/oNn4DNvXxHtm7kzAZ4.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.132’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 06:58:14 2018 from 192.168.116.135
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM2:~$
== Connected and exited ====>

=== Now let me connect to ===>
====From Ans-ControlMachine ======>
==== TO VM2 =================>
vskumar@ubuntu:~/.ssh$ ssh vskumar@192.168.116.135
The authenticity of host ‘192.168.116.135 (192.168.116.135)’ can’t be established.
ECDSA key fingerprint is SHA256:/HtM2RyrOSeFO01WW3d1S5fcB9mBM7MApniY54Nq4k4.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.135’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.135’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

vskumar@VM2:~$ cat /etc/hostname
VM2
vskumar@VM2:~$
vskumar@VM2:~$ exit
logout
Connection to 192.168.116.135 closed.
vskumar@ubuntu:~/.ssh$
===== Connected to VM2 and exited ===>

== SSh key added in VM2 ===>
====From Ans-ControlMachine ======>
vskumar@ubuntu:~/.ssh$
vskumar@ubuntu:~/.ssh$ ssh ssh-copy-id vskumar@192.168.116.135
ssh: Could not resolve hostname ssh-copy-id: Name or service not known
vskumar@ubuntu:~/.ssh$ sudo ssh-copy-id vskumar@192.168.116.135
[sudo] password for vskumar:
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: “/home/vskumar/.ssh/id_rsa.pub”
The authenticity of host ‘192.168.116.135 (192.168.116.135)’ can’t be established.
ECDSA key fingerprint is SHA256:/HtM2RyrOSeFO01WW3d1S5fcB9mBM7MApniY54Nq4k4.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed — if you are prompted now it is to install the new keys
vskumar@192.168.116.135’s password:

Number of key(s) added: 1

Now try logging into the machine, with: “ssh ‘vskumar@192.168.116.135′”
and check to make sure that only the key(s) you wanted were added.

vskumar@ubuntu:~/.ssh$
===== So now, we have made correct ssh connection ====>
=== with VM2 also ============================>

Now, let us try with VM3 as below:

=== Status of VM3 ====>
vskumar@VM3:~$ cat /etc/hostname
VM3
vskumar@VM3:~$ ssh -V
OpenSSH_7.2p2 Ubuntu-4ubuntu2.2, OpenSSL 1.0.2g 1 Mar 2016
vskumar@VM3:~$
vskumar@VM3:~$ ssh vskumar@192.168.116.135
The authenticity of host ‘192.168.116.135 (192.168.116.135)’ can’t be established.
ECDSA key fingerprint is SHA256:/HtM2RyrOSeFO01WW3d1S5fcB9mBM7MApniY54Nq4k4.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.135’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.135’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 07:13:50 2018 from 192.168.116.132
vskumar@VM2:~$ cat /etc/hostname
VM2
vskumar@VM2:~$
vskumar@VM2:~$ ssh vskumar@192.168.116.132
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 07:13:07 2018 from 192.168.116.132
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM2:~$
vskumar@VM2:~$ exit
logout
Connection to 192.168.116.135 closed.
vskumar@VM3:~$
vskumar@VM3:~$ ssh vskumar@192.168.116.132
The authenticity of host ‘192.168.116.132 (192.168.116.132)’ can’t be established.
ECDSA key fingerprint is SHA256:sIDDAzkiGiTCzpGHOTEU3QbG/oNn4DNvXxHtm7kzAZ4.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘192.168.116.132’ (ECDSA) to the list of known hosts.
vskumar@192.168.116.132’s password:
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.10.0-28-generic x86_64)

* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage

437 packages can be updated.
251 updates are security updates.

Last login: Sat May 26 07:35:04 2018 from 192.168.116.135
vskumar@ubuntu:~$ cat /etc/hostname
Ans-ControlMachine
vskumar@ubuntu:~$ exit
logout
Connection to 192.168.116.132 closed.
vskumar@VM3:~$
== So, we could connect from VM3 ====>
=== To all 3 other VMs ==============>
== The issues is resolved for ssh in VM3 ===>

Now, we are ready to use these ssh connection made machines for Ansible future exercises.

 

In the following video I have demonstrated with trouble shoot methods also:

26.DevOps:How to install Apache-Ant for Ubuntu ?:

Ant-Logo

 

 

In this blog, I would like to demonstrate the Apache-Ant installtion on Ubuntu.

What are the pre-requisites:
You need to have JDK 8/9 in your Ubuntu machine.
If you do not have it please visit my blog to get the installation instructions.
Please go through my JENKINS Instllation blog.
It has JDK installation procedure also.
URL: https://vskumar.blog/2017/11/25/1-devops-jenkins2-9-installation-with-java-9-on-windows-10/

How to uninstall existing ant?:
Step1:
I have ant installed in my ubuntu VM.
1st let me remove it and restart the install process:
We need to use the below command:
sudo apt-get remove ant
===== Screen display =====>
vskumar@ubuntu:~$ sudo apt-get remove ant
[sudo] password for vskumar:
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages will be REMOVED:
ant ant-optional
0 upgraded, 0 newly installed, 2 to remove and 4 not upgraded.
After this operation, 3,108 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database … 236912 files and directories currently installed.)
Removing ant-optional (1.9.6-1ubuntu1) …
Removing ant (1.9.6-1ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
========= Ant is Removed ===>

Step2:
=== Checking Ant version ===>
vskumar@ubuntu:~$ ant -v
The program ‘ant’ is currently not installed. You can install it by typing:
sudo apt install ant
vskumar@ubuntu:~$ D
===Now there is no Ant setup ===>
Looks like; still the ant is existing.

Step3:
Also please let us note the following:
If we want to delete configuration and/or data files of ant from Ubuntu Xenial completely,
then the below command will work:
sudo apt-get purge ant
== Screen display ===>
vskumar@ubuntu:~$ sudo apt-get purge ant
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following packages will be REMOVED:
ant* ant-optional*
0 upgraded, 0 newly installed, 2 to remove and 4 not upgraded.
After this operation, 3,108 kB disk space will be freed.
Do you want to continue? [Y/n] y
(Reading database … 236912 files and directories currently installed.)
Removing ant-optional (1.9.6-1ubuntu1) …
Removing ant (1.9.6-1ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
vskumar@ubuntu:~$
======================>

Now, let us check it.
=== Check the version now also ===>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ant -v
bash: /usr/bin/ant: No such file or directory
vskumar@ubuntu:~$
=================================>

Still you if you feel ant older version is there, we can follow the below step also:
To delete configuration and/or data files of ant and it’s dependencies from Ubuntu Xenial
then we should execute the below command:
sudo apt-get purge –auto-remove ant

Now, we will see how to install, configure and compile ant latest version1.10.1 ?:

Step1:
We need to update the packages/repos in Ubuntu VM as below:
sudo apt-get update
==== Screen display ======>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt-get update
[sudo] password for vskumar:
Hit:1 http://archive.ubuntu.com/ubuntu xenial InRelease
Hit:2 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial InRelease
Hit:3 http://ppa.launchpad.net/webupd8team/java/ubuntu xenial InRelease
Get:4 https://download.docker.com/linux/ubuntu xenial InRelease [65.8 kB]
Ign:5 https://apt.datadoghq.com stable InRelease
Get:6 https://apt.datadoghq.com stable Release [4,525 B]
Get:7 https://apt.datadoghq.com stable Release.gpg [819 B]
Ign:8 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial InRelease
Ign:9 https://pkg.jenkins.io/debian-stable binary/ InRelease
Ign:10 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial InRelease
Get:11 https://pkg.jenkins.io/debian-stable binary/ Release [2,042 B]
Get:12 https://pkg.jenkins.io/debian-stable binary/ Release.gpg [181 B]
Ign:13 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial Release
Ign:14 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial Release
Get:15 https://download.docker.com/linux/ubuntu xenial/edge amd64 Packages [4,793 B]
Ign:15 https://download.docker.com/linux/ubuntu xenial/edge amd64 Packages
Ign:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
Get:23 https://apt.datadoghq.com stable/6 amd64 Packages [2,447 B]
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Get:15 https://download.docker.com/linux/ubuntu xenial/edge amd64 Packages [4,521 B]
Ign:15 https://download.docker.com/linux/ubuntu xenial/edge amd64 Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Get:15 https://download.docker.com/linux/ubuntu xenial/edge amd64 Packages [29.9 kB]
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Get:29 https://pkg.jenkins.io/debian-stable binary/ Packages [12.7 kB]
Ign:29 https://pkg.jenkins.io/debian-stable binary/ Packages
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Get:29 https://pkg.jenkins.io/debian-stable binary/ Packages [11.9 kB]
Ign:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Ign:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Err:16 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 Packages
403 Forbidden
Ign:17 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 all Packages
Ign:18 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en_US
Ign:19 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 Translation-en
Ign:20 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:21 https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Err:22 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 Packages
403 Forbidden
Ign:24 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 all Packages
Ign:25 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en_US
Ign:26 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 Translation-en
Ign:27 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 amd64 DEP-11 Metadata
Ign:28 https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial/test-17.06 DEP-11 64×64 Icons
Fetched 118 kB in 35s (3,328 B/s)
Reading package lists… Done
W: The repository ‘https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu xenial Release’ does not have a Release file.
N: Data from such a repository can’t be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: The repository ‘https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu xenial Release’ does not have a Release file.
N: Data from such a repository can’t be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch https://storebits.docker.com/ee/ubuntu/<subscription-id>/ubuntu/dists/xenial/test-17.06/binary-amd64/Packages 403 Forbidden
E: Failed to fetch https://storebits.docker.com/ee/ubuntu/vskumardocker/ubuntu/dists/xenial/test-17.06/binary-amd64/Packages 403 Forbidden
E: Some index files failed to download. They have been ignored, or old ones used instead.
vskumar@ubuntu:~$
====================================>

Step2:
Now, We can get the install file of ant with the below command:
sudo apt-get install ant
==== Screen Display =====>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt-get install ant
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
ant-optional
Suggested packages:
ant-doc ant-gcj default-jdk | java-compiler | java-sdk ant-optional-gcj
antlr javacc jython libbcel-java libbsf-java libgnumail-java libjdepend-java
liboro-java libregexp-java
The following NEW packages will be installed:
ant ant-optional
0 upgraded, 2 newly installed, 0 to remove and 4 not upgraded.
Need to get 0 B/2,205 kB of archives.
After this operation, 3,108 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Selecting previously unselected package ant.
(Reading database … 236678 files and directories currently installed.)
Preparing to unpack …/ant_1.9.6-1ubuntu1_all.deb …
Unpacking ant (1.9.6-1ubuntu1) …
Selecting previously unselected package ant-optional.
Preparing to unpack …/ant-optional_1.9.6-1ubuntu1_all.deb …
Unpacking ant-optional (1.9.6-1ubuntu1) …
Processing triggers for man-db (2.7.5-1) …
Setting up ant (1.9.6-1ubuntu1) …
Setting up ant-optional (1.9.6-1ubuntu1) …
vskumar@ubuntu:~$
==========================>

Step3:
Now let me check its version.
===== Version check ===>
vskumar@ubuntu:~$ ant -v
Apache Ant(TM) version 1.9.6 compiled on July 8 2015
Trying the default build file: build.xml
Buildfile: build.xml does not exist!
Build failed
vskumar@ubuntu:~$
====================>

Step4:
We need to Install Apache Ant on Ubuntu 16.04 using SDKMan.
SDKMAN is a tool which can be usd to manage parallel versions of multiple
Software Development Kits on most Unix based systems.
The same way, we can leverage SDKMAN to install Apache Ant on Ubuntu 16.04.
Using the below command:
sdk install ant
Before doing this I need to install SDK in my ubuntu VM.

===== Screen display =====>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ curl -s “https://get.sdkman.io&#8221; | bash

-+syyyyyyys:
`/yho:` -yd.
`/yh/` +m.
.oho. hy .`
.sh/` :N` `-/o` `+dyyo:.
.yh:` `M- `-/osysoym :hs` `-+sys: hhyssssssssy+
.sh:` `N: ms/-“ yy.yh- -hy. `.N-““““+N.
`od/` `N- -/oM- ddd+` `sd: hNNm -N:
:do` .M. dMMM- `ms. /d+` `NMMs `do
.yy- :N` “`mMMM. – -hy. /MMM: yh
`+d+` `:/oo/` `-/osyh/ossssssdNMM` .sh: yMMN` /m.
-dh- :ymNMMMMy `-/shmNm-`:N/-.“ `.sN /N- `NMMy .m/
`oNs` -hysosmMMMMydmNmds+-.:ohm : sd` :MMM/ yy
.hN+ /d: -MMMmhs/-.` .MMMh .ss+- `yy` sMMN` :N.
:mN/ `N/ `o/-` :MMMo +MMMN- .` `ds mMMh do
/NN/ `N+….–:/+oooosooo+:sMMM: hMMMM: `my .m+ -MMM+ :N.
/NMo -+ooooo+/:-….`…:+hNMN. `NMMMd` .MM/ -m: oMMN. hs
-NMd` :mm -MMMm- .s/ -MMm. /m- mMMd -N.
`mMM/ .- /MMh. -dMo -MMMy od. .MMMs..—yh
+MMM. sNo`.sNMM+ :MMMM/ sh`+MMMNmNm+++-
mMMM- /–ohmMMM+ :MMMMm. `hyymmmdddo
MMMMh. ““ `-+yy/`yMMM/ :MMMMMy -sm:.“..-:-.`
dMMMMmo-.“““..-:/osyhddddho. `+shdh+. hMMM: :MmMMMM/ ./yy/` `:sys+/+sh/
.dMMMMMMmdddddmmNMMMNNNNNMMMMMs sNdo- dMMM- `-/yd/MMMMm-:sy+. :hs- /N`
`/ymNNNNNNNmmdys+/::—-/dMMm: +m- mMMM+ohmo/.` sMMMMdo- .om: `sh
`.—–+/.` `.-+hh/` `od. NMMNmds/ `mmy:` +mMy `:yy.
/moyso+//+ossso:. .yy` `dy+:` .. :MMMN+—/oys:
/+m: `.-:::-` /d+ +MMMMMMMNh:`
+MN/ -yh. `+hddhy+.
/MM+ .sh:
:NMo -sh/
-NMs `/yy:
.NMy `:sh+.
`mMm` ./yds-
`dMMMmyo:-.““.-:oymNy:`
+NMMMMMMMMMMMMMMMMms:`
-+shmNMMMNmdy+:`

Now attempting installation…

Looking for a previous installation of SDKMAN…
Looking for unzip…
Looking for zip…
Looking for curl…
Looking for sed…
Installing SDKMAN scripts…
Create distribution directories…
Getting available candidates…
Prime the config file…
Download script archive…
######################################################################## 100.0%
Extract script archive…
Install scripts…
Set version to 5.6.3+299 …
Attempt update of interactive bash profile on regular UNIX…
Added sdkman init snippet to /home/vskumar/.bashrc
Attempt update of zsh profile…
Updated existing /home/vskumar/.zshrc

All done!

Please open a new terminal, or run the following in the existing one:

source “/home/vskumar/.sdkman/bin/sdkman-init.sh”

Then issue the following command:

sdk help

Enjoy!!!
vskumar@ubuntu:~$
== SDK installed =====>
We need to use the below command:
=====>
vskumar@ubuntu:~$ source “$HOME/.sdkman/bin/sdkman-init.sh”
vskumar@ubuntu:~$
======>

Now, let us check SDK Version.
===== SDK Version checking ====>
vskumar@ubuntu:~$ sdk version
==== BROADCAST =================================================================
* 09/05/18: sbt 1.1.5 released on SDKMAN! #scala
* 09/05/18: Springboot 2.0.2.RELEASE released on SDKMAN! #springboot
* 09/05/18: Springboot 1.5.13.RELEASE released on SDKMAN! #springboot
================================================================================

SDKMAN 5.6.3+299
vskumar@ubuntu:~$
==========================>

Step5:

Now, let us use the below command:
sdk install ant

=== Screen display ==>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sdk install ant

 

Downloading: ant 1.10.1

In progress…

######################################################################## 100.0%

Installing: ant 1.10.1
Done installing!

 

Setting ant 1.10.1 as default.
vskumar@ubuntu:~$
vskumar@ubuntu:~$
=================>

Step6:
Now, let us check the ant’s latest version:

== Screen display ===>
vskumar@ubuntu:~$ ant -v
Apache Ant(TM) version 1.10.1 compiled on February 2 2017
Trying the default build file: build.xml
Buildfile: build.xml does not exist!
Build failed
vskumar@ubuntu:~$
== Now version change you can see after SDK usage ===>

Step7:
How to Create ANT_HOME Environment Variables?:

Create an ant.sh file at /etc/profile.d folder (you can use vi with below command)

== Let us see the files===>
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ ls /etc/profile.d
appmenu-qt5.sh bash_completion.sh vte-2.91.sh
apps-bin-path.sh cedilla-portuguese.sh
vskumar@ubuntu:~$
==========================>
There is no ant.sh file.

sudo vi /etc/profile.d/ant.sh
Enter the follow content to the file:

export ANT_HOME=/usr/local/ant
export PATH=${ANT_HOME}/bin:${PATH}
Save the file.
====== ant.sh file creation ===>
vskumar@ubuntu:~$ sudo vim /etc/profile.d/ant.sh
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo cat /etc/profile.d/ant.sh

export ANT_HOME=/usr/local/ant
export PATH=${ANT_HOME}/bin:${PATH}
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ls /etc/profile.d
ant.sh apps-bin-path.sh cedilla-portuguese.sh
appmenu-qt5.sh bash_completion.sh vte-2.91.sh
vskumar@ubuntu:~$
============ Contents of ant.sh=====>

Step8:
We need to activate the above environment variables.
We can do that by log out and log in again or simply run below command:
source /etc/profile
==== Screen display ===>
vskumar@ubuntu:~$ source /etc/profile
vskumar@ubuntu:~$
=======================>

Now let us check the ant version after doing the above steps to observe the change:

==== Display ==>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ant -version
Apache Ant(TM) version 1.10.1 compiled on February 2 2017
vskumar@ubuntu:~$
== Now error now =====>

Finally, we have configured Apache Ant(TM) version 1.10.1 and compiled successfully.

For Ant installation on windows 10 visit my blog:

https://vskumar.blog/2018/05/12/24-devops-how-to-install-apache-ant-for-windows-10/

25.DevOps:How to install Apache-Maven for Windows 10 ?

Apache-Maven Logo

With reference to my previous blog for Maven installation on Ubuntu:
https://vskumar.blog/2018/05/05/21-devops-how-to-install-maven-3-3-9-on-ubuntu-linux/

In this blog, I have shown the steps for Maven installation on
Windows 10.

Step1:
Goto the site: http://maven.apache.org/download.cgi
You can find the file: apache-maven-3.5.3-bin.zip
Save it to your desired location.

Step2:
Unzip it and it show have created the folder as below:
E:\apache-maven-3.5.3-bin

Note: You can replace this folder path with your Maven path.

It should have the following files/folders:

E:\apache-maven-3.5.3-bin>dir/p
Volume in drive E is New Volume
Volume Serial Number is 1870-3E6A

Directory of E:\apache-maven-3.5.3-bin

05/12/2018 01:40 PM <DIR> .
05/12/2018 01:40 PM <DIR> ..
05/12/2018 01:40 PM <DIR> apache-maven-3.5.3
0 File(s) 0 bytes
3 Dir(s) 33,347,407,872 bytes free

E:\apache-maven-3.5.3-bin>
E:\apache-maven-3.5.3-bin>cd apache*
E:\apache-maven-3.5.3-bin\apache-maven-3.5.3>
E:\apache-maven-3.5.3-bin\apache-maven-3.5.3>dir/p
Volume in drive E is New Volume
Volume Serial Number is 1870-3E6A

Directory of E:\apache-maven-3.5.3-bin\apache-maven-3.5.3

05/12/2018 01:40 PM <DIR> .
05/12/2018 01:40 PM <DIR> ..
05/12/2018 01:40 PM <DIR> bin
05/12/2018 01:40 PM <DIR> boot
05/12/2018 01:40 PM <DIR> conf
05/12/2018 01:40 PM <DIR> lib
05/12/2018 01:40 PM 20,959 LICENSE
05/12/2018 01:40 PM 182 NOTICE
05/12/2018 01:40 PM 2,544 README.txt
3 File(s) 23,685 bytes
6 Dir(s) 33,347,407,872 bytes free

E:\apache-maven-3.5.3-bin\apache-maven-3.5.3>

Step3:
Let us update the windows system/environment variables:

Check for M2_HOME variable. If it is not there,
create a new one and add the below:
Variable Name : M2_HOME
Variable Value : E:\apache-maven-3.5.3-bin\apache-maven-3.5.3

In your system variables,
if you have MAVEN_HOME as avriable you need update its value also.
Now, append this path to your PATH variable also.

Step4:
Now, how to verify the installed Maven version ?:
Open a fresh windows command prompt.
Type mvn -version
You should see the screen output as below wuth its 3.5.3 version:
Microsoft Windows [Version 10.0.16299.431]
(c) 2017 Microsoft Corporation. All rights reserved.

C:\Users\Toshiba>mvn -version
Apache Maven 3.5.3 (3383c37e1f9e9b3bc3df5050c29c8aff9f295297; 2018-02-25T01:19:05+05:30)
Maven home: E:\apache-maven-3.5.3-bin\apache-maven-3.5.3
Java version: 9.0.1, vendor: Oracle Corporation
Java home: D:\Java\jdk-9.0.1
Default locale: en_US, platform encoding: Cp1252
OS name: “windows 10”, version: “10.0”, arch: “amd64”, family: “windows”

C:\Users\Toshiba>

If you are getting the above version display;

So it means you have the correct/latest Maven version in your machine.

 

23.DevOps: How to install Ansible on Ubuntu [Linux] VM ?

 

ansible-logo.png

In this blog, I would like to demonstrate  “Installing Ansible on Ubuntu VM”.

At the End of this blog you can see the demonstrated Video.

Let us follow the below steps:

Step 1:
To get Ansible for Ubuntu is to add the project’s PPA (personal package archive) to ubuntu system.
We can add the Ansible PPA by typing the following command:

$sudo apt-add-repository ppa:ansible/ansible

=== Screen output ====>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt-add-repository ppa:ansible/ansible
[sudo] password for vskumar:
Ansible is a radically simple IT automation platform that makes your applications and systems easier to deploy.
Avoid writing scripts or custom code to deploy and update your applications— automate in a language that
approaches plain English, using SSH, with no agents to install on remote systems.

http://ansible.com/
More info: https://launchpad.net/~ansible/+archive/ubuntu/ansible
Press [ENTER] to continue or ctrl-c to cancel adding it

gpg: keyring `/tmp/tmpzhb6yoiy/secring.gpg’ created
gpg: keyring `/tmp/tmpzhb6yoiy/pubring.gpg’ created
gpg: requesting key 7BB9C367 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpzhb6yoiy/trustdb.gpg: trustdb created
gpg: key 7BB9C367: public key “Launchpad PPA for Ansible, Inc.” imported
gpg: Total number processed: 1
gpg: imported: 1 (RSA: 1)
OK
vskumar@ubuntu:~$
========= Added Ansible to PPA ===>
Step 2:
Now, let us refresh ubuntu [VM] system package index, so that it is aware of the packages available in the PPA.
Then, we can install the software.
We need to follow the below commands:
$sudo apt-get update
$sudo apt-get install ansible
==== Update package=======>
vskumar@ubuntu:~$ sudo apt-get update
Get:1 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial InRelease [18.0 kB]
Hit:2 https://download.docker.com/linux/ubuntu xenial InRelease
Hit:3 http://archive.ubuntu.com/ubuntu xenial InRelease
Hit:4 http://ppa.launchpad.net/webupd8team/java/ubuntu xenial InRelease
Get:5 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial/main amd64 Packages [540 B]
Ign:6 https://pkg.jenkins.io/debian-stable binary/ InRelease
Get:7 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial/main i386 Packages [540 B]
Hit:8 https://pkg.jenkins.io/debian-stable binary/ Release
Get:10 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial/main Translation-en [344 B]
Fetched 19.5 kB in 2s (7,857 B/s)
Reading package lists… Done
vskumar@ubuntu:~$
===== Updated =====>

Step 3:
Now, let us install Ansible as below:
==== Installing Ansible =====>
vskumar@ubuntu:~$ sudo apt-get install ansible
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
python-ecdsa python-httplib2 python-jinja2 python-markupsafe python-paramiko
sshpass
Suggested packages:
python-jinja2-doc
The following NEW packages will be installed:
ansible python-ecdsa python-httplib2 python-jinja2 python-markupsafe
python-paramiko sshpass
0 upgraded, 7 newly installed, 0 to remove and 0 not upgraded.
Need to get 3,001 kB of archives.
After this operation, 24.1 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-markupsafe amd64 0.23-2build2 [15.5 kB]
Get:2 http://ppa.launchpad.net/ansible/ansible/ubuntu xenial/main amd64 ansible all 2.4.3.0-1ppa~xenial [2,690 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-jinja2 all 2.8-1 [109 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-ecdsa all 0.13-2 [34.0 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-paramiko all 1.16.0-1 [109 kB]
Get:6 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-httplib2 all 0.9.1+dfsg-1 [34.2 kB]
Get:7 http://archive.ubuntu.com/ubuntu xenial/universe amd64 sshpass amd64 1.05-1 [10.5 kB]
Fetched 3,001 kB in 9s (306 kB/s)
Selecting previously unselected package python-markupsafe.
(Reading database … 218383 files and directories currently installed.)
Preparing to unpack …/python-markupsafe_0.23-2build2_amd64.deb …
Unpacking python-markupsafe (0.23-2build2) …
Selecting previously unselected package python-jinja2.
Preparing to unpack …/python-jinja2_2.8-1_all.deb …
Unpacking python-jinja2 (2.8-1) …
Selecting previously unselected package python-ecdsa.
Preparing to unpack …/python-ecdsa_0.13-2_all.deb …
Unpacking python-ecdsa (0.13-2) …
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Preparing to unpack …/python-paramiko_1.16.0-1_all.deb …
Unpacking python-paramiko (1.16.0-1) …
Selecting previously unselected package python-httplib2.
Preparing to unpack …/python-httplib2_0.9.1+dfsg-1_all.deb …
Unpacking python-httplib2 (0.9.1+dfsg-1) …
Selecting previously unselected package sshpass.
Preparing to unpack …/sshpass_1.05-1_amd64.deb …
Unpacking sshpass (1.05-1) …
Selecting previously unselected package ansible.
Preparing to unpack …/ansible_2.4.3.0-1ppa~xenial_all.deb …
Unpacking ansible (2.4.3.0-1ppa~xenial) …
Processing triggers for man-db (2.7.5-1) …
Setting up python-markupsafe (0.23-2build2) …
Setting up python-jinja2 (2.8-1) …
Setting up python-ecdsa (0.13-2) …
Setting up python-paramiko (1.16.0-1) …
Setting up python-httplib2 (0.9.1+dfsg-1) …
Setting up sshpass (1.05-1) …
Setting up ansible (2.4.3.0-1ppa~xenial) …
vskumar@ubuntu:~$
=== Ansible installation is done! ====>

Step 4:
Let us add the below python properties  also:

sudo apt-get install python-software-properties
== Installing python properties =======>
vskumar@ubuntu:/etc/ansible$ sudo apt-get install python-software-properties
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
python-apt python-pycurl
Suggested packages:
python-apt-dbg python-apt-doc libcurl4-gnutls-dev python-pycurl-dbg
python-pycurl-doc
The following NEW packages will be installed:
python-apt python-pycurl python-software-properties
0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 202 kB of archives.
After this operation, 927 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-apt amd64 1.1.0~beta1build1 [139 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial/main amd64 python-pycurl amd64 7.43.0-1ubuntu1 [43.3 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial/universe amd64 python-software-properties all 0.96.20 [20.1 kB]
Fetched 202 kB in 1s (181 kB/s)
Selecting previously unselected package python-apt.
(Reading database … 220895 files and directories currently installed.)
Preparing to unpack …/python-apt_1.1.0~beta1build1_amd64.deb …
Unpacking python-apt (1.1.0~beta1build1) …
Selecting previously unselected package python-pycurl.
Preparing to unpack …/python-pycurl_7.43.0-1ubuntu1_amd64.deb …
Unpacking python-pycurl (7.43.0-1ubuntu1) …
Selecting previously unselected package python-software-properties.
Preparing to unpack …/python-software-properties_0.96.20_all.deb …
Unpacking python-software-properties (0.96.20) …
Setting up python-apt (1.1.0~beta1build1) …
Setting up python-pycurl (7.43.0-1ubuntu1) …
Setting up python-software-properties (0.96.20) …
vskumar@ubuntu:/etc/ansible$
===== Installed python properties ======>

Step 5:
Let us check the version:
=== Checking ANSIBLE Version ===>
vskumar@ubuntu:~$ ansible –version
ansible 2.4.3.0
config file = /etc/ansible/ansible.cfg
configured module search path = [u’/home/vskumar/.ansible/plugins/modules’, u’/usr/share/ansible/plugins/modules’]
ansible python module location = /usr/lib/python2.7/dist-packages/ansible
executable location = /usr/bin/ansible
python version = 2.7.12 (default, Dec 4 2017, 14:50:18) [GCC 5.4.0 20160609]
vskumar@ubuntu:~$
=============================>
It means from the above display it is confirmed ansible is available.

Step 6:
The ansible is on the below dir:

======= Check List of files ===>
vskumar@ubuntu:~$ ls -lha /etc/ansible
total 48K
drwxr-xr-x 4 root root 4.0K Mar 6 08:52 .
drwxr-xr-x 142 root root 12K Mar 6 05:59 ..
-rw-r–r– 1 root root 19K Jan 31 15:21 ansible.cfg
drwxr-xr-x 2 root root 4.0K Mar 6 08:59 group_vars
-rw-r–r– 1 root root 1.2K Mar 6 08:20 hosts
drwxr-xr-x 2 root root 4.0K Jan 31 19:46 roles
vskumar@ubuntu:~$
========================>

Step 7:
Always it is better we need to have backup of the above files in a folder.
Now let me copy all of them as below:
Make a backup of all the files as below :
== Making backup ====>

vskumar@ubuntu:~$ sudo cp -R /etc/ansible ansplatform1

vskumar@ubuntu:~$ cd ansplatform1
vskumar@ubuntu:~/ansplatform1$ ls
ansible.cfg group_vars hosts roles
vskumar@ubuntu:~/ansplatform1$
===== Backup files ====>

Step 8:
In the above dir, let us modify ansible.cfg
to have the below line uncommented:
inventory = hosts
====Modifying ansible.cfg ====>
vskumar@ubuntu:~/ansplatform1$ sudo vim ansible.cfg
vskumar@ubuntu:~/ansplatform1$
======>

You can see part of the file as below :
=== Part of config file to update ====>
vskumar@ubuntu:/etc/ansible$ ls
ansible.cfg group_vars hosts roles
vskumar@ubuntu:/etc/ansible$ vim ansible
vskumar@ubuntu:/etc/ansible$
vskumar@ubuntu:/etc/ansible$ vim ansible.cfg
vskumar@ubuntu:/etc/ansible$

Updated line:
inventory = /etc/ansible/hosts

== Updated area only ===>

Step 9:

Configuring Ansible Hosts:
Ansible keeps track of all of the servers.
It knows about them through a “hosts” file.
We need to set up this file first, before we can begin to
communicate with our other computers.
Now let us see the current content of hosts file:
Using : $sudo cat /etc/ansible/hosts

====== The default Contents of hosts file ===>
vskumar@ubuntu:~$ sudo cat /etc/ansible/hosts
# This is the default ansible ‘hosts’ file.
#
# It should live in /etc/ansible/hosts
#
# – Comments begin with the ‘#’ character
# – Blank lines are ignored
# – Groups of hosts are delimited by [header] elements
# – You can enter hostnames or ip addresses
# – A hostname/ip can be a member of multiple groups

# Ex 1: Ungrouped hosts, specify before any group headers.

## green.example.com
## blue.example.com
## 192.168.100.1
## 192.168.100.10

# Ex 2: A collection of hosts belonging to the ‘webservers’ group

## [webservers]
## alpha.example.org
## beta.example.org
## 192.168.1.100
## 192.168.1.110

# If you have multiple hosts following a pattern you can specify
# them like this:

## www[001:006].example.com

# Ex 3: A collection of database servers in the ‘dbservers’ group

## [dbservers]
##
## db01.intranet.mydomain.net
## db02.intranet.mydomain.net
## 10.25.1.56
## 10.25.1.57

# Here’s another example of host ranges, this time there are no
# leading 0s:

## db-[99:101]-node.example.com

vskumar@ubuntu:~$
==================>

We can see a file that has a lot of example configurations,
none of them will actually work for us since these hosts are made up.
So to start with, let’s make sure they all are commented out on the
lines in this file by adding a “#” before each line.

We will keep these examples in the file only as they were to help us with
configuration.

If we want to implement more complex scenarios in the future these can be reused.

After making sure all of these lines are commented,
we can start adding our hosts in the hosts file.
To do our lab exercise;
Now, we need to identify our local hosts.
You can check your laptop or desktop ip as one host.
Another host you consider your ubuntu VM, where the current Ansible is configured.
For now, let us work with two hosts only.
In my systems:
To identify my ubuntu host1:
====== ifconfig =====>

vskumar@ubuntu:~$ ifconfig
docker0 Link encap:Ethernet HWaddr 02:42:06:95:ca:2d
inet addr:172.17.0.1 Bcast:172.17.255.255 Mask:255.255.0.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

ens33 Link encap:Ethernet HWaddr 00:0c:29:f8:40:61
inet addr:192.168.116.129 Bcast:192.168.116.255 Mask:255.255.255.0
inet6 addr: fe80::2fed:4aa:a6:34ad/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3621 errors:0 dropped:0 overruns:0 frame:0
TX packets:1342 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5111534 (5.1 MB) TX bytes:112090 (112.0 KB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:530 errors:0 dropped:0 overruns:0 frame:0
TX packets:530 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:47656 (47.6 KB) TX bytes:47656 (47.6 KB)

vskumar@ubuntu:~$
=======================>
I need to consider  my base ubuntu VM is as ‘192.168.116.129’
Hence my host1=192.168.116.129 from ens33
You can also check your VM IP.

Now, let me check my local host [laptop] ip:

====== IPCONFIG info from Laptop CMD =====>
Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::197c:6a85:f86:a3e4%20
IPv4 Address. . . . . . . . . . . : 192.168.137.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
======================>
Let me check the ip connection from my Ubuntu VM.
=== Testing laptop ip from VM ====>
vskumar@ubuntu:~$ ping 192.168.137.1
PING 192.168.137.1 (192.168.137.1) 56(84) bytes of data.
64 bytes from 192.168.137.1: icmp_seq=1 ttl=128 time=3.89 ms
64 bytes from 192.168.137.1: icmp_seq=2 ttl=128 time=1.15 ms
64 bytes from 192.168.137.1: icmp_seq=3 ttl=128 time=1.19 ms
64 bytes from 192.168.137.1: icmp_seq=4 ttl=128 time=1.38 ms
64 bytes from 192.168.137.1: icmp_seq=5 ttl=128 time=1.15 ms
64 bytes from 192.168.137.1: icmp_seq=6 ttl=128 time=1.26 ms
64 bytes from 192.168.137.1: icmp_seq=7 ttl=128 time=1.13 ms
64 bytes from 192.168.137.1: icmp_seq=8 ttl=128 time=1.13 ms
64 bytes from 192.168.137.1: icmp_seq=9 ttl=128 time=1.39 ms
64 bytes from 192.168.137.1: icmp_seq=10 ttl=128 time=1.29 ms
64 bytes from 192.168.137.1: icmp_seq=11 ttl=128 time=1.26 ms
64 bytes from 192.168.137.1: icmp_seq=12 ttl=128 time=1.14 ms
64 bytes from 192.168.137.1: icmp_seq=13 ttl=128 time=1.22 ms
64 bytes from 192.168.137.1: icmp_seq=14 ttl=128 time=1.37 ms
64 bytes from 192.168.137.1: icmp_seq=15 ttl=128 time=1.14 ms
^C
— 192.168.137.1 ping statistics —
15 packets transmitted, 15 received, 0% packet loss, time 14032ms
rtt min/avg/max/mdev = 1.134/1.411/3.899/0.672 ms
vskumar@ubuntu:~$
==========>
Now, I consider my host2 = 192.168.137.1

Let me ping my VM from Laptop CMD:
==== Pinging Ubuntu IP from CMD prompt =====>
C:\Users\Toshiba>ping 192.168.116.129

Pinging 192.168.116.129 with 32 bytes of data:
Reply from 192.168.116.129: bytes=32 time=2ms TTL=64
Reply from 192.168.116.129: bytes=32 time<1ms TTL=64
Reply from 192.168.116.129: bytes=32 time<1ms TTL=64
Reply from 192.168.116.129: bytes=32 time<1ms TTL=64

Ping statistics for 192.168.116.129:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 2ms, Average = 0ms

C:\Users\Toshiba>
====== Replied VM ====>

It means both hosts are working fine.
Now, below block we should add to our hosts file to connect them:

[servers]
host1 ansible_ssh_host=192.168.116.129
host2 ansible_ssh_host=192.168.137.1
We can consider two groups from these two hosts.
Let me check the files as below:
==== List the current files ====>

vskumar@ubuntu:/etc/ansible$ ls -l
total 28
-rw-r–r– 1 root root 19155 Jan 31 15:21 ansible.cfg
-rw-r–r– 1 root root 1016 Jan 31 15:21 hosts
drwxr-xr-x 2 root root 4096 Jan 31 19:46 roles
vskumar@ubuntu:/etc/ansible$
===============================>

Now, let me update the host file.
=== After adding the content of hosts file ===>
vskumar@ubuntu:/etc/ansible$ sudo vim hosts
[sudo] password for vskumar:
Sorry, try again.
[sudo] password for vskumar:
vskumar@ubuntu:/etc/ansible$
vskumar@ubuntu:/etc/ansible$ tail -10 hosts

# Here’s another example of host ranges, this time there are no
# leading 0s:

## db-[99:101]-node.example.com

[servers]
host1 ansible_ssh_host=192.168.116.129
host2 ansible_ssh_host=192.168.137.1
vskumar@ubuntu:/etc/ansible$
== You can see the lst 3 lines of the hosts file ===>

We also need to add the group name as below in the hosts file.

[group_name]
alias ansible_ssh_host=your_server_ip

Here, the group_name is an organizational tag that you will refer to any servers listed
under it with one word.
The alias is just a name to refer to that server.
Now let me add the above lines in hosts above the servers line as below.
[ansible_test1]
alias ansible_ssh_host=192.168.116.129
===== Hosts updated – latest ===>
vskumar@ubuntu:/etc/ansible$ sudo vim hosts
vskumar@ubuntu:/etc/ansible$
vskumar@ubuntu:/etc/ansible$ tail -10 hosts
# leading 0s:

## db-[99:101]-node.example.com
[ansible_test1]
alias ansible_ssh_host=192.168.116.129

[servers]
host1 ansible_ssh_host=192.168.116.129
host2 ansible_ssh_host=192.168.137.1

vskumar@ubuntu:/etc/ansible$
==============================>

Now let me goto ansible dir:
======>
vskumar@ubuntu:~$ cd /etc/ansible
vskumar@ubuntu:/etc/ansible$
======>

Assuming in our Ansible test scenario,
we are imagining that we have two servers we are going to control with Ansible.
These servers are accessible from the Ansible server by typing:
$ssh root@your_server_ip

Means as:
$ssh root@192.168.116.129

==============>
vskumar@ubuntu:/etc/ansible$ ssh root@192.168.116.129
ssh: connect to host 192.168.116.129 port 22: Connection refused
vskumar@ubuntu:/etc/ansible$
==============>
TROUBLE SHOOT THE HOSTS:
=== Trouble shoot ===>
vskumar@ubuntu:/etc/ansible$ ansible -m ping all
host1 | UNREACHABLE! => {
“changed”: false,
“msg”: “Failed to connect to the host via ssh: ssh: connect to host 192.168.116.129 port 22: Connection refused\r\n”,
“unreachable”: true
}
alias | UNREACHABLE! => {
“changed”: false,
“msg”: “Failed to connect to the host via ssh: ssh: connect to host 192.168.116.129 port 22: Connection refused\r\n”,
“unreachable”: true
}
host2 | UNREACHABLE! => {
“changed”: false,
“msg”: “Failed to connect to the host via ssh: \r\n ****USAGE WARNING****\r\n\r\nThis is a private computer system. This computer system, including all\r\nrelated equipment, networks, and network devices (specifically including\r\nInternet access) are provided only for authorized use. This computer system\r\nmay be monitored for all lawful purposes, including to ensure that its use\r\nis authorized, for management of the system, to facilitate protection against\r\nunauthorized access, and to verify security procedures, survivability, and\r\noperational security. Monitoring includes active attacks by authorized entities\r\nto test or verify the security of this system. During monitoring, information\r\nmay be examined, recorded, copied and used for authorized purposes. All\r\ninformation, including personal information, placed or sent over this system\r\nmay be monitored.\r\n\r\nUse of this computer system, authorized or unauthorized, constitutes consent\r\nto monitoring of this system. Unauthorized use may subject you to criminal\r\nprosecution. Evidence of unauthorized use collected during monitoring may be\r\nused for administrative, criminal, or other adverse action. Use of this system\r\nconstitutes consent to monitoring for these purposes.\r\n\r\n\r\nPermission denied (publickey,password,keyboard-interactive).\r\n”,
“unreachable”: true
}
vskumar@ubuntu:/etc/ansible$
===============>
The reason for the above error is;
With our current settings, we tried to connect to any of these hosts with Ansible,
the command failed.
This is because your SSH key is embedded for the root user on the remote systems
and Ansible will by default try to connect as your current user.
A connection attempt will get the above error.

To rectify it;
We can create a file that tells all of the servers in the “servers” group to connect
using the root user.

To do this, we will create a directory in the Ansible configuration structure called group_vars.
Let us use the below dir commands:
$sudo mkdir /etc/ansible/group_vars

========================>
vskumar@ubuntu:/etc/ansible$ sudo mkdir /etc/ansible/group_vars
vskumar@ubuntu:/etc/ansible$ ls -l
total 32
-rw-r–r– 1 root root 19155 Jan 31 15:21 ansible.cfg
drwxr-xr-x 2 root root 4096 Mar 6 08:52 group_vars
-rw-r–r– 1 root root 1158 Mar 6 08:20 hosts
drwxr-xr-x 2 root root 4096 Jan 31 19:46 roles
vskumar@ubuntu:/etc/ansible$
=================>
Within this folder, we can create YAML-formatted files for each group we want to configure.
By using below command:
$sudo vim /etc/ansible/group_vars/servers
We can put our configuration in here. YAML files start with “—“, so make sure you don’t forget that part.

Below Code:

ansible_ssh_user: root

==========>
udo vim /etc/ansible/group_vars/servers
vskumar@ubuntu:/etc/ansible$ cat /etc/ansible/group_vars/servers


ansible_ssh_user: root
vskumar@ubuntu:/etc/ansible$
=======================>

NOTE:
If you want to specify configuration details for every server, regardless of group association, you can put those details in a file at: 

/etc/ansible/group_vars/all.

Individual hosts can be configured by creating files under a directory at: /etc/ansible/host_vars.

Assuming this helped you to configure your Ansible.

Please leave your positive comment for others also to follow.

You can see next blog on ssh setup and usage from the below url:

https://vskumar.blog/2018/05/26/27-devopsworking-with-ssh-for-ansible-usage/

I have made a video for Ansible installation using Ubuntu 18.04 VM:

16. DevOps: Working with Git on Ubuntu 16.04/18.04 VMs

Git-logo

All the below commands were copied from the Ubuntu 16.04 VM.

You can see the below video on how to uninstall/install git from Ubuntu 18.04.

You can use all the below commands from 8.04 VM also.

In this GIT exercise, I would like to present the below lab sessions for git in an Ubuntu 16.04 VM for the people who attended my sessions so far.
1. How to install git in ubuntu [linux] ?:
2. How To Set Up Git ?:
3. How to check the config file content? :
4. How to clone a project from an url ?:
5. How to Create a test dir or folder for git project?:
6. How initiate the git for the current folder or dir in linux ?:
7. How to Create local files and check the status in the current git folder?:
8. How to commit the files into a local repository and check their status ?:
9. How to commit files into local repo with a message ?:
10. How to check the history of the local git repository ?:
11. How to identify the difference of two commit ids ?:
12. How to check and operate the staged files in local repository ?:
13. What are the ultimate format of the git log ?:
14. How to setup aliases for different git commands?:
15. How to use tags and operate for different versions in a repository?:
16. How to revert back the changes to older version ?:
17. How to cancel the committed changes? :
18. How to reset the reverted changes through commit from the branch? :

19. Working with git directory:

     20. Working with git branches and master :

     21. How to Merge latest objects into single branch ?:

1. How to install git in ubuntu [linux] ?:

$sudo apt-get update

$sudo apt-get install git

2. How To Set Up Git ?:
$git config –global user.name “Your Name”

$git config –global user.email “youremail@domain.com”

Ex:
git config –global user.kumar2018 “Vskumar”
git config –global user.email “vskumar35@gmail.com”

==== Screen output for the above commands==>
vskumar@ubuntu:~$ git config –global user.kumar2018 “Vskumar”
vskumar@ubuntu:~$ git config –global user.email “vskumar35@gmail.com”
vskumar@ubuntu:~$ git config –list
user.kumar2018=Vskumar
user.email=vskumar35@gmail.com
vskumar@ubuntu:~$
===========>
3. How to check the config file content? :

$cat ~/.gitconfig
==== Output of config file ===>
vskumar@ubuntu:~$ cat ~/.gitconfig
[user]
kumar2018 = Vskumar
email = vskumar35@gmail.com
vskumar@ubuntu:~$
=============>

4. How to clone a project from an url ?: Let us clone one project as below:
$git clone https://github.com/vskumar2017/VSKTestproject1

=== Screen outout ==>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo git clone https://github.com/vskumar2017/VSKTestproject1
Cloning into ‘VSKTestproject1’…
remote: Counting objects: 57, done.
remote: Total 57 (delta 0), reused 0 (delta 0), pack-reused 57
Unpacking objects: 100% (57/57), done.
Checking connectivity… done.
vskumar@ubuntu:~$
vskumar@ubuntu:~$ ls
data-volume1 examples.desktop Pictures VSKTestproject1
Desktop flask-test Public
Documents jdk-9.0.4_linux-x64_bin.tar.gz Templates
Downloads Music Videos
vskumar@ubuntu:~$
=====================>
5. How to Create a test dir or folder for git project?:

=============>
vskumar@ubuntu:~$ mkdir test-git
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ ls
data-volume1 examples.desktop Pictures Videos
Desktop flask-test Public VSKTestproject1
Documents jdk-9.0.4_linux-x64_bin.tar.gz Templates
Downloads Music test-git
vskumar@ubuntu:~$
vskumar@ubuntu:~$
vskumar@ubuntu:~$ cd test-git
vskumar@ubuntu:~/test-git$ ls
vskumar@ubuntu:~/test-git$
=======>
6. How initiate the git for the current folder or dir in linux ?:
== Initialize the current dir for git init===>
vskumar@ubuntu:~/test-git$ git init
Initialized empty Git repository in /home/vskumar/test-git/.git/
vskumar@ubuntu:~/test-git$
========>

7. How to Create local files and check the status in the current git folder?:
== Create a text file========>
vskumar@ubuntu:~/test-git$ echo “Testing line1 for git ..” >> test1.txt vskumar@ubuntu:~/test-git$ cat test1.txt Testing line1 for git .. vskumar@ubuntu:~/test-git$ ls -l
total 4
-rw-rw-r– 1 vskumar vskumar 25 Feb 24 04:03 test1.txt

vskumar@ubuntu:~/test-git$ git status On branch master Initial commit Untracked files: (use “git add <file>…” to include in what will be committed) test1.txt nothing added to commit but untracked files present (use “git add” to track) vskumar@ubuntu:~/test-git$
===== Add a new file====>
vskumar@ubuntu:~/test-git$ git add test1.txt
vskumar@ubuntu:~/test-git$ git status
On branch master
Initial commit

Changes to be committed:
(use “git rm –cached <file>…” to unstage)

new file: test1.txt

vskumar@ubuntu:~/test-git$

===========>

8. How to commit the files into a local repository and check their status ?:

Now, let us do simple commit the file to the local repo.

$git commit -m “First Commit”
=== Commite output ==>
vskumar@ubuntu:~/test-git$ git commit -m “First Commit”
[master (root-commit) 56ccc1e] First Commit
1 file changed, 1 insertion(+)
create mode 100644 test1.txt
vskumar@ubuntu:~/test-git$
======================>
We can check the current status:

=== status after commit ===>
vskumar@ubuntu:~/test-git$ git status
On branch master
nothing to commit, working directory clean
vskumar@ubuntu:~/test-git$
==========>

== Added a new message ===>
vskumar@ubuntu:~/test-git$ echo ‘Testing line2 for git—->’ >> test1.txt
vskumar@ubuntu:~/test-git$ cat test1.txt
Testing line1 for git ..
Testing line2 for git—->
vskumar@ubuntu:~/test-git$
===============>

=== Current status ===>
vskumar@ubuntu:~/test-git$ git status
On branch master
Changes not staged for commit:
(use “git add <file>…” to update what will be committed)
(use “git checkout — <file>…” to discard changes in working directory)

modified: test1.txt

no changes added to commit (use “git add” and/or “git commit -a”)
vskumar@ubuntu:~/test-git$
=====================>
Now, add these two files:
git add test1.txt
git add test2.txt

=== Add and check status for two files ==>
vskumar@ubuntu:~/test-git$ git add test1.txt
vskumar@ubuntu:~/test-git$ git add test2.txt
vskumar@ubuntu:~/test-git$ git status
On branch master
Changes to be committed:
(use “git reset HEAD <file>…” to unstage)

modified: test1.txt
new file: test2.txt

vskumar@ubuntu:~/test-git$
====================================>
9. How to commit files into local repo with a message ?:

Commit these two files:

git commit -m “Committed:Changes for test1.txt and test2.txt”

==== Committed changes and status ===>
vskumar@ubuntu:~/test-git$ git commit -m “Committed:Changes for test1.txt and test2.txt”
[master 2a7192d] Committed:Changes for test1.txt and test2.txt
2 files changed, 2 insertions(+)
create mode 100644 test2.txt
vskumar@ubuntu:~/test-git$ git status
On branch master
nothing to commit, working directory clean
vskumar@ubuntu:~/test-git$
======================================>

Now, let us test the add command . prompt by having 2 or more files.

=== Updated two files ==>
vskumar@ubuntu:~/test-git$ cat test1.txt
Testing line1 for git ..
Testing line2 for git—->
Testing test1.tx for add . function
vskumar@ubuntu:~/test-git$ cat test2.txt
File Test2: Testing for Git commit –>
Testing test2.tx for add . function
vskumar@ubuntu:~/test-git$
=============>
Let us check the status:
==== Status ==>

vskumar@ubuntu:~/test-git$ git status
On branch master
Changes not staged for commit:
(use “git add <file>…” to update what will be committed)
(use “git checkout — <file>…” to discard changes in working directory)

modified: test1.txt
modified: test2.txt

no changes added to commit (use “git add” and/or “git commit -a”)
vskumar@ubuntu:~/test-git$
===============>

Now to add these two file together we need to use ‘git addd .’
== Added all files ===>
vskumar@ubuntu:~/test-git$
vskumar@ubuntu:~/test-git$ git add .
vskumar@ubuntu:~/test-git$ git status
On branch master
Changes to be committed:
(use “git reset HEAD <file>…” to unstage)

modified: test1.txt
modified: test2.txt

vskumar@ubuntu:~/test-git$
============>
Now let us commit the changes of one file at a time.

=== test1.txt commitment===>
vskumar@ubuntu:~/test-git$ git commit test1.txt -m ‘Committed test1.txt 3rd change’
[master 6bfd9b0] Committed test1.txt 3rd change
1 file changed, 1 insertion(+)
vskumar@ubuntu:~/test-git$ ^C
============================>
Now, let us check the status:

=======>
vskumar@ubuntu:~/test-git$
vskumar@ubuntu:~/test-git$ git status
On branch master
Changes to be committed:
(use “git reset HEAD <file>…” to unstage)

modified: test2.txt

vskumar@ubuntu:~/test-git$
========>
In git we can check the history by using ‘git log’ command.

=== Histroy ====>
vskumar@ubuntu:~/test-git$ git log
commit 69282e8d8c07e7cbc68e93b16df1d943d3b518d5
Author: Vsk <vskumar35@gmail.com>
Date: Sat Feb 24 06:49:27 2018 -0800

Committed test2.txt 3rd change

commit 6bfd9b045c352f13c36d8f82f12567058a8bb468
Author: Vsk <vskumar35@gmail.com>
Date: Sat Feb 24 06:46:24 2018 -0800

Committed test1.txt 3rd change

commit 2a7192dcdd1a123b8164f0d48dd0631645cf0630
Author: Vsk <vskumar35@gmail.com>
Date: Sat Feb 24 06:32:03 2018 -0800

Committed:Changes for test1.txt and test2.txt

commit 56ccc1ec9ae7db9f97e3a08e5488a64b4f130f1b
Author: Vsk <vskumar35@gmail.com>
Date: Sat Feb 24 06:08:42 2018 -0800

First Commit
vskumar@ubuntu:~/test-git$
=====================>
10. How to check the history of the local git repository ?:

In git we can check the history by using ‘git log’ command. It can give entire committed history with the relevant comments. If we use ‘git log –pretty=oneline’ it gives only chekcsums for different times commited occasions with commit the messages.

If we use ‘git log –pretty=oneline’ it gives only chekcsums for different times commited occasions with commit the messages.

=== Output for pretty ===>
vskumar@ubuntu:~/test-git$ git log –pretty=oneline
69282e8d8c07e7cbc68e93b16df1d943d3b518d5 Committed test2.txt 3rd change
6bfd9b045c352f13c36d8f82f12567058a8bb468 Committed test1.txt 3rd change
2a7192dcdd1a123b8164f0d48dd0631645cf0630 Committed:Changes for test1.txt and test2.txt
56ccc1ec9ae7db9f97e3a08e5488a64b4f130f1b First Commit
vskumar@ubuntu:~/test-git$
==============>

We can also check the commitments by author also using
‘git log –pretty=oneline –author=<your name>’

git log –pretty=oneline –author=kumar

============>
vskumar@ubuntu:~/test-git$ git log –pretty=oneline –author=kumar
69282e8d8c07e7cbc68e93b16df1d943d3b518d5 Committed test2.txt 3rd change
6bfd9b045c352f13c36d8f82f12567058a8bb468 Committed test1.txt 3rd change
2a7192dcdd1a123b8164f0d48dd0631645cf0630 Committed:Changes for test1.txt and test2.txt
56ccc1ec9ae7db9f97e3a08e5488a64b4f130f1b First Commit
============>
Let me give wrong user name to test:
=== Wrong user name ====>
vskumar@ubuntu:~/test-git$ git log –pretty=oneline –author=kumar1
vskumar@ubuntu:~/test-git$ git log –pretty=oneline –author=kumar202
vskumar@ubuntu:~/test-git$
= No files committed for the above users ==>

We can see more detail about a particular commit through show command.
The command ‘git log’ yields a sequential history of the individual commits within the repository.
Then you need to collect the commit id.

=== git show =====>
vskumar@ubuntu:~/test-git$ git show 56ccc1ec9ae7db9f97e3a08e5488a64b4f130f1b
commit 56ccc1ec9ae7db9f97e3a08e5488a64b4f130f1b
Author: Vsk <vskumar35@gmail.com>
Date: Sat Feb 24 06:08:42 2018 -0800

First Commit

diff –git a/test1.txt b/test1.txt
new file mode 100644
index 0000000..73b0484
— /dev/null
+++ b/test1.txt
@@ -0,0 +1 @@
+Testing line1 for git ..
vskumar@ubuntu:~/test-git$
=============================>
11. How to identify the difference of two commit ids ?:
The diff command recalls both full commit ID names and run ‘git diff’

git diff 2a7192dcdd1a123b8164f0d48dd0631645cf0630 6bfd9b045c352f13c36d8f82f12567058a8bb468

== Output of two commit diffs ==>
vskumar@ubuntu:~/test-git$ git diff 2a7192dcdd1a123b8164f0d48dd0631645cf0630 6bfd9b045c352f13c36d8f82f12567058a8bb468
diff –git a/test1.txt b/test1.txt
index 931bb8b..b9132c1 100644
— a/test1.txt
+++ b/test1.txt
@@ -1,2 +1,3 @@
Testing line1 for git ..
Testing line2 for git—->
+Testing test1.tx for add . function
vskumar@ubuntu:~/test-git$
==============================>
12. How to check and operate the staged files in local repository ?:

We can use the below command:
git ls-files –stage

=== Stage of current files ===>
vskumar@ubuntu:~/test-git$
vskumar@ubuntu:~/test-git$ git ls-files –stage
100644 b9132c1dd4ac08fa9c1e3dea5d7100e33557ad20 0 test1.txt
100644 0866cfd2c7ac9bf17f0a0590551a3580359e7250 0 test2.txt
vskumar@ubuntu:~/test-git$
========================>
=== Rm and later files stage ==>
vskumar@ubuntu:~/test-git$ git rm –cached test1.txt
rm ‘test1.txt’
vskumar@ubuntu:~/test-git$ git ls-files –stage
100644 0866cfd2c7ac9bf17f0a0590551a3580359e7250 0 test2.txt
vskumar@ubuntu:~/test-git$
vskumar@ubuntu:~/test-git$ git rm –cached test1.txt
rm ‘test1.txt’
vskumar@ubuntu:~/test-git$ git ls-files –stage
100644 0866cfd2c7ac9bf17f0a0590551a3580359e7250 0 test2.txt
vskumar@ubuntu:~/test-git$
=====>
You can see the removed file is back into dir:
== Status of removed file ==>
vskumar@ubuntu:~/test-git$ git status
On branch master
Changes to be committed:
(use “git reset HEAD <file>…” to unstage)
deleted: test1.txt
Untracked files:
(use “git add <file>…” to include in what will be committed)

test1.txt
vskumar@ubuntu:~/test-git$
=== It need to be be added and committed ====>
vskumar@ubuntu:~/test-git$ git add .
vskumar@ubuntu:~/test-git$ git status
On branch master
nothing to commit, working directory clean
vskumar@ubuntu:~/test-git$
======= It need to be added only===.

====== list the stage files =>
vskumar@ubuntu:~/test-git$
vskumar@ubuntu:~/test-git$ git ls-files –stage
100644 b9132c1dd4ac08fa9c1e3dea5d7100e33557ad20 0 test1.txt
100644 0866cfd2c7ac9bf17f0a0590551a3580359e7250 0 test2.txt
vskumar@ubuntu:~/test-git$
=========================>
13. What are the ultimate format of the git log ?:
We can use the ultimate format of the log as: git log –pretty=format:”%h %ad | %s%d [%an]” –graph –date=short

===== Screen output ==========>
vskumar@ubuntu:~$ cd test-git vskumar@ubuntu:~/test-git$ pwd /home/vskumar/test-git vskumar@ubuntu:~/test-git$ git log –pretty=format:”%h %ad | %s%d [%an]” –graph –date=short * 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master) [Vsk] * 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk] * 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk] * 56ccc1e 2018-02-24 | First Commit [Vsk] vskumar@ubuntu:~/test-git$

==============================>

14. How to setup aliases for different git commands?:

If there is a common and complex the Git command you type frequently, consider setting up a simple Git alias for it.

We can use the below common aliases:

git config –global alias.ci commit

git config –global alias.st status

git config –global alias.br branch

git config –global alias.hist “log –pretty=format:’%h %ad | %s%d [%an]’ –graph –date=short”

Once you setup the above aliases for git commands you need to use them only, instead of commands.

Like; for command: ‘log –pretty=format:’%h %ad | %s%d [%an]’ –graph –date=short You need to use git hist, etc.

You also need to remember them well. Once you setup the above aliases for git commands you need to use them only instead of commands.

Like; for command: ‘log –pretty=format:”%h %ad | %s%d [%an]” –graph –date=short’

You need to use git hist, etc. You also need to remember them well.

Let us try one command for branch:

===== Screen output ==========>

vskumar@ubuntu:~$ cd test-git

vskumar@ubuntu:~/test-git$ pwd /home/vskumar/test-git

vskumar@ubuntu:~/test-git$ git log –pretty=format:”%h %ad | %s%d [%an]” –graph –date=short

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master) [Vsk]

*6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk] vskumar@ubuntu:~/test-git$ ==========================>

=== History =======>

vskumar@ubuntu:~/test-git$ git log –pretty=format:”%h %ad | %s%d [%an]” –graph –date=short

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$ git config –global alias.hist “log –pretty=format:’%h %ad | %s%d [%an]’ –grap h –date=short”

==== With alias hist ========>

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

==========================>

15. How to use tags and operate for different versions in a repository?:

Tags for previous versions of git: W

We can tag latest committed versions from a local repo to reuse them later stages. Let’s tag the version prior to the current version with the name v1.

First, we will checkout the previous version. Instead of looking up the hash, we are going to use the  notation indicating “the parent of v1”. git tag v1

=== You can see the tagging process for the latest commit ===>

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$ git tag v1

vskumar@ubuntu:~/test-git$ git checkout v1

Note: checking out ‘v1’. You are in ‘detached HEAD’ state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by performing another checkout. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -b with the checkout command again. Example: git checkout -b <new-branch-name> HEAD is now at 69282e8… Committed test2.txt 3rd change

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD, tag: v1, master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$ git status

HEAD detached at v1 nothing to commit, working directory clean vskumar@ubuntu:~/test-git$

================================>

Now, let us add a line to test1.txt and commit it.

===== Screen output ===>

vskumar@ubuntu:~/test-git$ ls -l total 8

-rw-rw-r– 1 vskumar vskumar 88 Feb 24 06:37 test1.txt

-rw-rw-r– 1 vskumar vskumar 75 Feb 24 06:37 test2.txt

vskumar@ubuntu:~/test-git$ git status

HEAD detached at v1 nothing to commit, working directory clean vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ echo ‘Testing test1.txt for tagging v2’ >> test1.txt vskumar@ubuntu:~/test-git$ cat test1.txt

Testing line1 for git .. Testing line2 for git—->

Testing test1.tx for add . function

Testing test1.txt for tagging v2

vskumar@ubuntu:~/test-git$ git status

HEAD detached at v1 Changes not staged for commit: (use “git add <file>…” to update what will be committed) (use “git checkout — <file>…” to discard changes in working directory) modified: test1.txt no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$

========================>

Now let me add and commit

=== Add and commit for tagging 2nd time ===>

vskumar@ubuntu:~/test-git$ git add .

vskumar@ubuntu:~/test-git$ git status

HEAD detached at v1 Changes to be committed: (use “git reset HEAD <file>…” to unstage) modified: test1.txt

vskumar@ubuntu:~/test-git$ git commit -m ‘Added for tagging 2nd time’

[detached HEAD 0bec7c0] Added for tagging 2nd time 1 file changed, 1 insertion(+) vskumar@ubuntu:~/test-git$ git status HEAD detached from v1 nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

===============>

Now, let us tag 2nd time :

== You can see two versions are tagged ===>

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git hist

* 0bec7c0 2018-02-24 | Added for tagging 2nd time (HEAD) [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1, master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$ git tag v2

vskumar@ubuntu:~/test-git$ git hist

* 0bec7c0 2018-02-24 | Added for tagging 2nd time (HEAD, tag: v2) [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1, master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

===========================>

Now let us check the latest version of test1.txt content.

=== Latest version test1.txt ===>

vskumar@ubuntu:~/test-git$ ls -l

total 8 -rw-rw-r– 1

vskumar vskumar 121 Feb 24 20:58 test1.txt -rw-rw-r– 1 vskumar vskumar 75 Feb 24 06:37 test2.txt

vskumar@ubuntu:~/test-git$ cat test1.txt

Testing line1 for git .. Testing line2 for git—-> Testing test1.tx for add . function Testing test1.txt for tagging v2

vskumar@ubuntu:~/test-git$

============>

Now, let us checkout the older version to test the content of test1.txt. using : git checkout v1

====== Chekout v1 to track changes ====>

vskumar@ubuntu:~/test-git$ git checkout v1

Previous HEAD position was 0bec7c0… Added for tagging 2nd time HEAD is now at 69282e8… Committed test2.txt 3rd change

vskumar@ubuntu:~/test-git$ cat test1.txt

Testing line1 for git .. Testing line2 for git—->

Testing test1.tx for add . function

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git status

HEAD detached at v1 nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

=== We can see the older version content only===>

===== We can see the hist and make the current master checkout s v1 ===> vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD, tag: v1, master) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git checkout

master Switched to branch ‘master’

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master, tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk] vskumar@ubuntu:~/test-git$ vskumar@ubuntu:~/test-git$ git status On branch master nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

==============================>

16. How to revert back the changes to older version ?:

Now, let us understand on how to revertback the changes in a local file.

We can use reset command to bring back the previous version. If you have a modified object in the working dir and want to revertback to older version you can follow the below steps.

The reset command resets the buffer zone to HEAD. This clears the buffer zone from the changes that we have just staged. The reset command (default) does not change the working directory. Hence, the working directory still contains unwanted comments.

We can use the checkout command from the previous tutorial to remove unwanted changes from working directory.

===== to revertback Reset the modified file and checkout that file only =====> vskumar@ubuntu:~/test-git$ git status On branch master nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$ echo ‘Testing for reset Head command’ >> test1.txt vskumar@ubuntu:~/test-git$ git status On branch master Changes not staged for commit: (use “git add <file>…” to update what will be committed) (use “git checkout — <file>…” to discard changes in working directory) modified: test1.txt no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$ git reset HEAD test1.txt Unstaged changes after reset: M test1.txt

vskumar@ubuntu:~/test-git$ git status On branch master Changes not staged for commit: (use “git add <file>…” to update what will be committed) (use “git checkout — <file>…” to discard changes in working directory) modified: test1.txt no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$

=== Finally, You can see the older version contents only ====>

17. How to cancel the committed changes? :

We have seen on how to cancel the modified files.

Now we can check on how to revert back the committed changes in the local git repo.

== Let us see the current hist ===>

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD -> master, tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=================>

Now let us consider v1 to revert back.

We need to use command:git revert HEAD. When we use this command it will open a editor by showing the details.

We can save it using ‘wq!’ like in vi/vim.

===== Output =======>

vskumar@ubuntu:~/test-git$ git revert HEAD

[master fdc40ac] Revert “Committed test2.txt 3rd change” 1 file changed, 1 deletion(-)

vskumar@ubuntu:~/test-git$

===================>

Now, let us check hist

=== git hist ====>

vskumar@ubuntu:~/test-git$ git hist

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” (HEAD -> master) [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=================>

============ Exercise ====================>

If you want to can do an Exercise: You can checkout the committed version. You can add a test to text1 file and commit it. Again you can use the same lab practice.

============ You can revert back also =====>

18. How to reset the reverted changes through commit from the branch? :

Check the previous screen display for the usage of revert command.

Now, if we have decided to reset the changes we can use the command: ‘git reset –hard v1’

=== Screen output for resetting reverted commit=====>

vskumar@ubuntu:~/test-git$ git reset –hard v1

HEAD is now at 69282e8 Committed test2.txt 3rd change

vskumar@ubuntu:~/test-git$ git hist

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD, tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=====================>

We can check the committed history using the below command: git hist –all

==== Screen output git hist –all ===>

vskumar@ubuntu:~/test-git$ git hist –all

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” (master) [Vsk] |

* 0bec7c0 2018-02-24 | Added for tagging 2nd time (tag: v2) [Vsk] |

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD, tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=====================>

You can also observe the reverted information.

We can also drop the tags as below: git tag -d v1

===== Output for tag removal ====>

vskumar@ubuntu:~/test-git$ git tag -d v2

Deleted tag ‘v2’ (was 0bec7c0)

vskumar@ubuntu:~/test-git$ git hist –all

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” (master) [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (HEAD, tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

==========So, now v2 tag is removed ========>

You can also see the config file as below:

=== Config file ====>

vskumar@ubuntu:~/test-git$ cat .git/config

[core] repositoryformatversion = 0 filemode = true bare = false logallrefupdates = true vskumar@ubuntu:~/test-git$

=====This configuration file is created for each individual project.===============>

19. Working with git directory:

 

Every Git project will have directories and files.

We can see the git dir items:

==================== Git dir items ===>

vskumar@ubuntu:~/test-git$ ls -l -C .git

branches        config       HEAD   index  logs     ORIG_HEAD

COMMIT_EDITMSG  description  hooks  info   objects  refs

vskumar@ubuntu:~/test-git$

======Root folder of git project =====>

 

We can explore the objects dir to check the objects details.

using ls -l -C .git/objects

 

==== Output ====>

vskumar@ubuntu:~/test-git$ ls -l -C .git/objects

07  0b  44  4f  68  6b  92  b0  bd  fd    pack

08  2a  47  56  69  73  93  b9  e0  info

vskumar@ubuntu:~/test-git$

================>

 

We can see a lot of folders named with two characters.

The first two letters sha1 hash of the object stored in git are the directory names.

 

What is SHA1 ?:

The SHA-1 (Secure Hash Algorithm 1) is a cryptographic hash function.  

It takes an input and produces a 160-bit (20-byte) hash value known as a message digest to the object.

Typically it is rendered as a hexadecimal number, with 40 digits long.

 

Now, let us see it by inquiring our database objects from the above listed items:

Using the below command we can check the files in dir.

ls -C .git/objects/<dir>   — The dir is the two characters of the above shown values.

==== Checking one dir ====>

vskumar@ubuntu:~/test-git$ ls -l  -C .git/objects/07

5e722b3161a24fd5adcefb574b5360118abbef

vskumar@ubuntu:~/test-git$ ls -l  -C .git/objects/92

d62ee30d26c444d85b3d81a4e2b8b69e0f093f

vskumar@ubuntu:~/test-git$

==== You can see 40 digits size hexadecimal value of objects in 07 and 92 objects dir====>

 

Note, we have seen the config file from the previous exercises.

Now, We will check the branches and tags as below commands:

 

ls .git/refs

ls .git/refs/heads

ls .git/refs/tags

cat .git/refs/tags/v1

 

== Checking branches and tags ===>

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ ls .git/refs

heads  tags

vskumar@ubuntu:~/test-git$ ls .git/refs/heads

master

vskumar@ubuntu:~/test-git$ ls .git/refs/tags

v1

vskumar@ubuntu:~/test-git$ cat .git/refs/tags/v1

69282e8d8c07e7cbc68e93b16df1d943d3b518d5

vskumar@ubuntu:~/test-git$

=================================>

 

Let us note;  each file corresponds to the tag previously created using the git tag command.

Its content is a hash commit attached to the tag.

We have only one branch, and everything we see here in this folder is a master branch.

Now, let us check what the HEAD file contains?:

using :cat .git/HEAD

 

==============>

vskumar@ubuntu:~/test-git$ cat .git/HEAD

683ed74fda585e10f38111ebb4c84026d5678290

vskumar@ubuntu:~/test-git$

=============>

 

Let us search for the last committed items:

We can explore the structure of the database objects

using SHA1 hashes for searching the content in the repository.

 

The below command should find the last commit in the repository.

======= SHA hash of git hist ==>

vskumar@ubuntu:~/test-git$ git hist –max-count=1

* 683ed74 2018-02-24 | Added updated test1.txt (HEAD) [Vsk]

vskumar@ubuntu:~/test-git$

==============================>

SHA1 hash is probably different on our systems from this git format.

Now, let us check the last commit details.

Using the below commands:

git cat-file -t <hash>

git cat-file -p <hash>

 

==== SHA1 content and the tree details ===>

vskumar@ubuntu:~/test-git$ git cat-file -t 683ed74

commit

vskumar@ubuntu:~/test-git$ git cat-file -p 683ed74

tree 44298909c5e8873c5870f9f1ca77951ea4e028eb

parent 69282e8d8c07e7cbc68e93b16df1d943d3b518d5

author Vsk <vskumar35@gmail.com> 1519544092 -0800

committer Vsk <vskumar35@gmail.com> 1519544092 -0800

Added updated test1.txt

vskumar@ubuntu:~/test-git$

==========================================>

Now, we can display the tree referenced in the above commit.

Using :git cat-file -p <treehash>

From the couple of characters shown for tree.

====== We can see the real files stored under git blob ====>

vskumar@ubuntu:~/test-git$ git cat-file -p 44298909

100644 blob 075e722b3161a24fd5adcefb574b5360118abbef test1.txt

100644 blob 0866cfd2c7ac9bf17f0a0590551a3580359e7250 test2.txt

vskumar@ubuntu:~/test-git$

================================================>

 

== See the contents for text1.txt also ===>

vskumar@ubuntu:~/test-git$ git cat-file -p 075e722b

Testing line1 for git ..

Testing line2 for git—->

Testing test1.tx for add . function

Checking for changing commit comment

vskumar@ubuntu:~/test-git$

====================================>

 

So we have seen the main branch to till the object content level.

 

20. Working with git branches and master :

 

Now, let us see the branches operation. We can create different branches as each developer

can have his/her own branch while working with the same or different objects.

Let us see the current statusof git project:

=========>

vskumar@ubuntu:~/test-git$ pwd

/home/vskumar/test-git

vskumar@ubuntu:~/test-git$ git status

HEAD detached from v1

Changes not staged for commit:

  (use “git add <file>…” to update what will be committed)

  (use “git checkout — <file>…” to discard changes in working directory)

 

modified:   test1.txt

modified:   test2.txt

 

Untracked files:

  (use “git add <file>…” to include in what will be committed)

 

class

test1.class

test1.java

 

no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$

======================>

 

Now, Let us create a new branch as below [using checkout] and test the operations.

 

git checkout -b testgitbr1

git status

 

====== We are just copied the same project as a branch ======>

vskumar@ubuntu:~/test-git$ git checkout -b testgitbr1

M test1.txt

M test2.txt

Switched to a new branch ‘testgitbr1’

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

Changes not staged for commit:

  (use “git add <file>…” to update what will be committed)

  (use “git checkout — <file>…” to discard changes in working directory)

 

modified:   test1.txt

modified:   test2.txt

 

Untracked files:

  (use “git add <file>…” to include in what will be committed)

 

class

test1.class

test1.java

 

no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$

==================>

Assume a developer want to add his own program.

Now, I would like to add the test1.java program into this new branch:

======= Adding new file ====>

vskumar@ubuntu:~/test-git$ git add test1.java

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

Changes to be committed:

  (use “git reset HEAD <file>…” to unstage)

 

new file:   test1.java

 

Changes not staged for commit:

  (use “git add <file>…” to update what will be committed)

  (use “git checkout — <file>…” to discard changes in working directory)

 

modified:   test1.txt

modified:   test2.txt

 

Untracked files:

  (use “git add <file>…” to include in what will be committed)

 

class

test1.class

 

vskumar@ubuntu:~/test-git$

=== New branch has a java program also ===>

Now, let me commit this file with a message:

 

git commit -m “Added a java program [test1.java] to new branch”

 

========>

vskumar@ubuntu:~/test-git$ git commit -m “Added a java program [test1.java] to new branch”

[testgitbr1 4e7baf8] Added a java program [test1.java] to new branch

 1 file changed, 11 insertions(+)

 create mode 100644 test1.java

vskumar@ubuntu:~/test-git$

=============>

Let us see the status:

 

=== Current status ====>

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

Changes not staged for commit:

  (use “git add <file>…” to update what will be committed)

  (use “git checkout — <file>…” to discard changes in working directory)

 

modified:   test1.txt

modified:   test2.txt

 

Untracked files:

  (use “git add <file>…” to include in what will be committed)

 

class

test1.class

 

no changes added to commit (use “git add” and/or “git commit -a”)

vskumar@ubuntu:~/test-git$

========================>

Now let me add all the modified files also with a commit:

 

=======>

vskumar@ubuntu:~/test-git$ git add .

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

Changes to be committed:

  (use “git reset HEAD <file>…” to unstage)

 

new file:   class

new file:   test1.class

modified:   test1.txt

modified:   test2.txt

 

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git commit -m “Added all 4 files [2-new and 2 modified]”

[testgitbr1 26b971b] Added all 4 files [2-new and 2 modified]

 4 files changed, 14 insertions(+), 4 deletions(-)

 create mode 100644 class

 create mode 100644 test1.class

 mode change 100644 => 100755 test1.txt

 mode change 100644 => 100755 test2.txt

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

== So, we have updated the new branch ====>

 

Now we need to navigate the available branches.

Let us apply git hist command and check the history as below:

== Checking the git project repo history ====>

vskumar@ubuntu:~/test-git$ git hist

* 26b971b 2018-03-05 | Added all 4 files [2-new and 2 modified] (HEAD -> testgitbr1) [Vsk]

* 4e7baf8 2018-03-05 | Added a java program [test1.java] to new branch [Vsk]

* 683ed74 2018-02-24 | Added updated test1.txt [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

== You can see the latest branch and commit messages===>

Now, let us toggle or do workaround between the branch and the master as below:

Please note so far we are with the testgitbr1 which is  branch.

Now let us use master as below:

git checkout master

==== Master ====>

vskumar@ubuntu:~/test-git$ git checkout master

Switched to branch ‘master’

vskumar@ubuntu:~/test-git$ git status

On branch master

nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

================>

 

Let us check some files and their content:

=== Checking master ===>

 vskumar@ubuntu:~/test-git$ cat test1.txt

Testing line1 for git ..

Testing line2 for git—->

Testing test1.tx for add . function

vskumar@ubuntu:~/test-git$ cat test1.java

cat: test1.java: No such file or directory

vskumar@ubuntu:~/test-git$

==========>

 

Now, let us switch to branch and check the files:

== You can see the difference from master ====>

vskumar@ubuntu:~/test-git$ git checkout testgitbr1

Switched to branch ‘testgitbr1’

vskumar@ubuntu:~/test-git$ git status

On branch testgitbr1

nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$ cat test1.java

 

class test1{

  public static void main(String args[]){

    System.out.println(“Hello Welcome to DevOps course”);

System.out.println(“Hope you are practicing well Jenkins 2.9”);

System.out.println(“Now, create a java object file through javac compiler”);

System.out.println(“Using Jenkins job creation”);

System.out.println(“Once it is created, you run it by java runtime”);

System.out.println(“Now, compare the console output with your expectation!!”);

  }

}

vskumar@ubuntu:~/test-git$ cat test1.txt

echo ‘Testing line1 for git ..’

echo ‘Testing line2 for git—->’

echo ‘Testing test1.tx for add . function’

echo ‘Checking for changing commit comment’

echo ‘For removal of old comment’

vskumar@ubuntu:~/test-git$

==Note the test1.txt has different content from master =====>

 

Now, let us try to add one README file into master.

I want to create the README file as below:

 

== README file content ===>

vskumar@ubuntu:~/test-git$ pwd

/home/vskumar/test-git

vskumar@ubuntu:~/test-git$ git checkout master

Switched to branch ‘master’

vskumar@ubuntu:~/test-git$ git status

On branch master

nothing to commit, working directory clean

vskumar@ubuntu:~/test-git$

vskumar@ubuntu:~/test-git$ touch README

vskumar@ubuntu:~/test-git$ echo “Testing Master and branches” >> README

vskumar@ubuntu:~/test-git$ cat README

Testing Master and branches

vskumar@ubuntu:~/test-git$ echo “Added this README file into master only” >> README

vskumar@ubuntu:~/test-git$ cat README

Testing Master and branches

Added this README file into master only

vskumar@ubuntu:~/test-git$

===================================>

Let us commit this file into master.

 

=== Status ====>

 

vskumar@ubuntu:~/test-git$ git status

On branch master

Untracked files:

  (use “git add <file>…” to include in what will be committed)

 

README

 

nothing added to commit but untracked files present (use “git add” to track)

vskumar@ubuntu:~/test-git$

=======>

 

Add and  Commit it with message :

 

==== Commit master ===>

 

vskumar@ubuntu:~/test-git$ git add README

vskumar@ubuntu:~/test-git$ git status

On branch master

Changes to be committed:

  (use “git reset HEAD <file>…” to unstage)

 

new file:   README

 

vskumar@ubuntu:~/test-git$

===== Added README ====>

Now, Commit:

 

==== Commit master ===>

vskumar@ubuntu:~/test-git$ git commit -m “Added README file into mater”

[master 1fad32b] Added README file into mater

 1 file changed, 2 insertions(+)

 create mode 100644 README

vskumar@ubuntu:~/test-git$

======================>

Now, let us view the current hist of master and branch as below with git hist –all:

 

== Current history ===>

 vskumar@ubuntu:~/test-git$ git hist –all

* 1fad32b 2018-03-05 | Added README file into mater (HEAD -> master) [Vsk]

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” [Vsk]

| * 26b971b 2018-03-05 | Added all 4 files [2-new and 2 modified] (testgitbr1) [Vsk]

| * 4e7baf8 2018-03-05 | Added a java program [test1.java] to new branch [Vsk]

| * 683ed74 2018-02-24 | Added updated test1.txt [Vsk]

|/  

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=== You can see on top last two commits of both master and branch =========>

 

21. How to Merge latest objects into single branch ?:

 

Now, we have two different branches. We can consolidate both branches versions and

merge them into a new branch for future developers to use them as one latest project.

Let us go back to the testgitbr1 branch and merge it with master by using the below commands.

git checkout testgitbr1

git merge master

================>

vskumar@ubuntu:~/test-git$ git checkout testgitbr1

Switched to branch ‘testgitbr1’

======>

When you use merge command a file opens in vi, just save it as it is.

==========================>

vskumar@ubuntu:~/test-git$ git merge master

Auto-merging test2.txt

Merge made by the ‘recursive’ strategy.

 README    | 2 ++

 test2.txt | 1 –

 2 files changed, 2 insertions(+), 1 deletion(-)

 create mode 100644 README

vskumar@ubuntu:~/test-git$

=================>

And let us see the current history:

git hist –all

 

===== History =====>

vskumar@ubuntu:~/test-git$ git hist –all

*   6b67f05 2018-03-05 | Merge branch ‘master’ into testgitbr1 (HEAD -> testgitbr1) [Vsk]

|\  

| * 1fad32b 2018-03-05 | Added README file into mater (master) [Vsk]

| * fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” [Vsk]

* | 26b971b 2018-03-05 | Added all 4 files [2-new and 2 modified] [Vsk]

* | 4e7baf8 2018-03-05 | Added a java program [test1.java] to new branch [Vsk]

* | 683ed74 2018-02-24 | Added updated test1.txt [Vsk]

|/  

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

== Let us check the above commit history also =============>

 

From the above exercise, we can conclude any developer can merge his/her current branch into master once they decide to release the code.

 

22. How to reset the earlier created branch from the local repository?:

 

We will see from this exercise, how a developer can reset the earlier branch.

We need to be on the branch now.

we should use ‘git checkout testgitbr1’

 

= Switching to testgitbr1 branch ==>

vskumar@ubuntu:~/test-git$ git checkout testgitbr1

Switched to branch ‘testgitbr1’

vskumar@ubuntu:~/test-git$

============>

Now. let us see the current history of the git local repo:

 

==== Git hist====>

 

vskumar@ubuntu:~/test-git$ git hist

*   6b67f05 2018-03-05 | Merge branch ‘master’ into testgitbr1 (HEAD -> testgitbr1) [Vsk]

|\  

| * 1fad32b 2018-03-05 | Added README file into mater (master) [Vsk]

| * fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” [Vsk]

* | 26b971b 2018-03-05 | Added all 4 files [2-new and 2 modified] [Vsk]

* | 4e7baf8 2018-03-05 | Added a java program [test1.java] to new branch [Vsk]

* | 683ed74 2018-02-24 | Added updated test1.txt [Vsk]

|/  

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

== Note, both branches info is available ===>

To remove the testgitbr1 branch we need to reset it.

git reset –hard <hash> —> Here the testgitbr1 branch 1st commit Hash is 4e7baf8.

So our command is; git reset –hard 4e7baf8

 

=== Resetting branch ===>

vskumar@ubuntu:~/test-git$ git reset –hard 4e7baf8

HEAD is now at 4e7baf8 Added a java program [test1.java] to new branch

==== Rsetting is done for branch ===>

Now let us check the hist all:

 

===== Hist all =====>

vskumar@ubuntu:~/test-git$ git hist –all

* 1fad32b 2018-03-05 | Added README file into mater (master) [Vsk]

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” [Vsk]

| * 4e7baf8 2018-03-05 | Added a java program [test1.java] to new branch (HEAD -> testgitbr1) [Vsk]

| * 683ed74 2018-02-24 | Added updated test1.txt [Vsk]

|/  

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

== Note;testgitbr1 branch is disappeared ====>

Now let us see the latest history.

So, this way any developer can create and merge a branch and later on it can be destroyed also.

 

23. How to add the current code to github?:

 

create a new repository or use the existing repo on the command line

Create your own github userid and a project in it.

Then you can create repository online. You will see set of commands display on the web page.

Follow them. Or follow as below:

 

Steps for Guthub access:

 

You need to set the project url as below:

========================>

vskumar@ubuntu:~/test-git$ git remote set-url origin https://github.com/vskumar2017/git-test1.git

vskumar@ubuntu:~/test-git$

========================>

Please see the below content, I have pushed the code to my account VSKUMAR2017 as below:

 

==== Pushed code to github account ====>

vskumar@ubuntu:~/test-git$ git push origin master –force

Username for ‘https://github.com&#8217;: VSKUMAR2017

Password for ‘https://VSKUMAR2017@github.com&#8217;:

Counting objects: 20, done.

Compressing objects: 100% (16/16), done.

Writing objects: 100% (20/20), 1.85 KiB | 0 bytes/s, done.

Total 20 (delta 2), reused 0 (delta 0)

remote: Resolving deltas: 100% (2/2), done.

To https://github.com/vskumar2017/git-test1.git

 * [new branch]      master -> master

vskumar@ubuntu:~/test-git$

====================>

 

I have gone throuhg my account and saw the below url:

https://github.com/vskumar2017/git-test1

 

=== As per the below hist it is stored ===>

vskumar@ubuntu:~/test-git$ git hist

* e3fab98 2018-03-05 | first commit (HEAD -> master) [Vsk]

* 1fad32b 2018-03-05 | Added README file into mater [Vsk]

* fdc40ac 2018-02-24 | Revert “Committed test2.txt 3rd change” [Vsk]

* 69282e8 2018-02-24 | Committed test2.txt 3rd change (tag: v1) [Vsk]

* 6bfd9b0 2018-02-24 | Committed test1.txt 3rd change [Vsk]

* 2a7192d 2018-02-24 | Committed:Changes for test1.txt and test2.txt [Vsk]

* 56ccc1e 2018-02-24 | First Commit [Vsk]

vskumar@ubuntu:~/test-git$

=====================>

I have done one more push:

 

==== One more push to github ===>

vskumar@ubuntu:~/test-git$ git checkout master

Switched to branch ‘master’

vskumar@ubuntu:~/test-git$ git add .

vskumar@ubuntu:~/test-git$ git commit -m “A shell sample added “

[master c61b3dd] A shell sample added

 1 file changed, 3 insertions(+)

 create mode 100644 sh1.sh

vskumar@ubuntu:~/test-git$ git push origin master –force

Username for ‘https://github.com&#8217;: VSKUMAR2017

Password for ‘https://VSKUMAR2017@github.com&#8217;:

Counting objects: 3, done.

Compressing objects: 100% (2/2), done.

Writing objects: 100% (3/3), 299 bytes | 0 bytes/s, done.

Total 3 (delta 1), reused 0 (delta 0)

remote: Resolving deltas: 100% (1/1), completed with 1 local object.

To https://github.com/vskumar2017/git-test1.git

   e3fab98..c61b3dd  master -> master

vskumar@ubuntu:~/test-git$

=========================>

 

I have see the below content on my guthub web page of url:https://github.com/vskumar2017/git-test1

===== Message ===>

sh1.sh  A shell sample added just now

======>

 Hope you enjoyed it technically!!

END OF LAB SESSION FOR Git

 

 Vcard-Shanthi Kumar V-v3

If you are keen practicing Mock interviews for a Job Description, Please read the below blog to contact:

https://vskumar.blog/2020/02/03/contact-for-aws-devops-sre-roles-mock-interview-prep-not-proxy-for-original-profile/

15. DevOps: How to setup jenkins 2.9 on Ubuntu-16.04 with jdk8 with a trouble shoot video guidance

jenkins

In continuation of blog related to Jenkins installation on Win10 url :https://vskumar.blog/2017/11/25/1-devops-jenkins2-9-installation-with-java-9-on-windows-10/

In this blog I would like to demonstrate on Jenkins 2.9 installation using Ubuntu 16.04 OS with JDK8. I used Ubuntu 16.04 VM.  You can use your standalone Ubuntu machine also.

At the end  a video link is given for this entire exercise…. with a job run…

[Note: If you are a student and in need of  Ubuntu 16.04 VM copy, I can share it. You need to send a request through linkedin with your identity please. At the bottom of this blog you can get my details.]

If you want to install Jenkins you need to have JDK in the Ubuntu machine.

You need to install JDK8 as 1st instance for Jenkins setup:

How to install JDK8?:

Step 1:-
Download JDK 8 tar.gz file from official website

Step 2:-
Extract contents using tar command

$tar -xzvf filename.tar.gz

Step 3 :-
Move Extracted file to /usr/local/java Directory
=====CLI Screen output ===>
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ cd /usr/local
vskumar@ubuntu:/usr/local$ ls
bin etc games include lib man sbin share src
vskumar@ubuntu:/usr/local$ mkdir java
mkdir: cannot create directory ‘java’: Permission denied
vskumar@ubuntu:/usr/local$ sudo mkdir java
[sudo] password for vskumar:
vskumar@ubuntu:/usr/local$ ls
bin etc games include java lib man sbin share src
vskumar@ubuntu:/usr/local$
vskumar@ubuntu:/usr/local$ cd java
vskumar@ubuntu:/usr/local/java$

vskumar@ubuntu:~$
vskumar@ubuntu:~$ ls
data-volume1 Downloads jdk-9.0.4_linux-x64_bin.tar.gz Public
Desktop examples.desktop Music Templates
Documents flask-test Pictures Videos
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$

vskumar@ubuntu:~/Downloads$ ls
firefox-57.0.tar.bz2 jdk1.8.0_161 jdk-8u161-linux-x64.tar.gz

vskumar@ubuntu:~/Downloads$ sudo mv jdk1.8.0_161 /usr/local/java
[sudo] password for vskumar:
vskumar@ubuntu:~/Downloads$ ls
firefox-57.0.tar.bz2 jdk-8u161-linux-x64.tar.gz
vskumar@ubuntu:~/Downloads$
vskumar@ubuntu:/usr/local/java$ pwd
/usr/local/java
vskumar@ubuntu:/usr/local/java$ ls -l
total 4
drwxr-xr-x 8 vskumar vskumar 4096 Dec 19 16:24 jdk1.8.0_161
vskumar@ubuntu:/usr/local/java$

==jdk8 unzipped files are moved into /usr/local/java ===>

Step 4: – Now,
Update Alternatives

$sudo update-alternatives –install “/usr/bin/java” “java” “/usr/local/java/jdk1.8.0_161/bin/java” 1

$sudo update-alternatives –install “/usr/bin/javac” “javac” “/usr/local/java/jdk1.8.0_161/bin/javac” 1

$sudo update-alternatives –install “/usr/bin/javaws” “javaws” “/usr/local/java/jdk1.8.0_161/bin/javaws” 1

=== Output===>

vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$ pwd
/usr/local/java/jdk1.8.0_161
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$ sudo update-alternatives –install “/usr/bin/java” “java” “/usr/local/java/jdk1.8.0_161/bin/java” 1
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$ sudo update-alternatives –install “/usr/bin/javac” “javac” “/usr/local/java/jdk1.8.0_161/bin/javac” 1
update-alternatives: using /usr/local/java/jdk1.8.0_161/bin/javac to provide /usr/bin/javac (javac) in auto mode
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$ sudo update-alternatives –install “/usr/bin/javaws” “javaws” “/usr/local/java/jdk1.8.0_161/bin/javaws” 1
update-alternatives: using /usr/local/java/jdk1.8.0_161/bin/javaws to provide /usr/bin/javaws (javaws) in auto mode
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$
==============>

Step 5 :-
Check Java version
$ java -version

======>
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$ java -version
java version “1.8.0_161”
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)
vskumar@ubuntu:/usr/local/java/jdk1.8.0_161$
====We have done JDKsetup ===>

Now, You can see “How to install Jenkins on Ubuntu 16.04?”:

For details Visit: https://wiki.jenkins.io/display/JENKINS/Installing+Jenkins+on+Ubuntu

Step1:
First, we need to add the jenkins repository key to the ubuntu system.

$ sudo wget -q -O – https://pkg.jenkins.io/debian/jenkins-ci.org.key | sudo apt-key add –

When the key is added, the system will return ‘OK’

Step2:
Now, we need to append the Debian package repository
address to the server’s sources.list:

$echo deb https://pkg.jenkins.io/debian-stable binary/ | sudo tee /etc/apt/sources.list

The screen ouput for the above steps:
=== Screen output of Step1 and Step2====>
vskumar@ubuntu:~$ sudo wget -q -O – https://pkg.jenkins.io/debian/jenkins-ci.org.key | sudo apt-key add –
OK
vskumar@ubuntu:~$ echo deb https://pkg.jenkins.io/debian-stable binary/ | sudo tee /etc/apt/sources.list
deb https://pkg.jenkins.io/debian-stable binary/
vskumar@ubuntu:~$ sudo apt-get update
===============>

When both of the above steps are executed, we’ll run update so that apt-get will use
the new repository:

Step3:
$sudo apt-get update

==== You will see the below screen output ===>
vskumar@ubuntu:~$ echo deb https://pkg.jenkins.io/debian-stable binary/ | sudo tee /etc/apt/sources.list
deb https://pkg.jenkins.io/debian-stable binary/
vskumar@ubuntu:~$ sudo apt-get update
Hit:1 https://download.docker.com/linux/ubuntu xenial InRelease
Ign:2 https://pkg.jenkins.io/debian-stable binary/ InRelease
Hit:3 https://pkg.jenkins.io/debian-stable binary/ Release
Reading package lists… Done
vskumar@ubuntu:~$
========================>

========>
vskumar@ubuntu:~$ sudo find . / jenkins | grep ‘jenkins’
find: ‘/run/user/1000/gvfs’: Permission denied
/var/lib/apt/lists/pkg.jenkins.io_debian-stable_binary_Packages
/var/lib/apt/lists/pkg.jenkins.io_debian-stable_binary_Release.gpg
/var/lib/apt/lists/pkg.jenkins.io_debian-stable_binary_Release
find: ‘jenkins’: No such file or directory
vskumar@ubuntu:~$
==============>

Step4:
Include JAVA_HOME = /usr/local/java/jdk1.8.0_161
in .shrc file.

Now, we will install Jenkins and its dependencies:

$sudo apt-get install jenkins
Whenyou run this command your might get the below error:
=== Dependecy issues ======>
vskumar@ubuntu:~$ sudo apt-get install jenkins
Reading package lists… Done
Building dependency tree
Reading state information… Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
jenkins : Depends: daemon but it is not installable
Depends: default-jre-headless (>= 2:1.8) or
java8-runtime-headless
E: Unable to correct problems, you have held broken packages.
vskumar@ubuntu:~$
======================>

To resolve this issued, Under Ubuntu Software tab, enable all the repositories.
The system updates all the packages/libs.

Visit for details:
https://askubuntu.com/questions/140246/how-do-i-resolve-unmet-dependencies-after-adding-a-ppa

After doing the repositories updates as mentioned above, I have re-executed the install command:

==== Screen Output of Jenkins installation ====
vskumar@ubuntu:~$ sudo apt-get install jenkins
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
ca-certificates-java daemon default-jre-headless java-common
openjdk-8-jre-headless
Suggested packages:
default-jre openjdk-8-jre-jamvm fonts-dejavu-extra fonts-ipafont-gothic
fonts-ipafont-mincho ttf-wqy-microhei | ttf-wqy-zenhei fonts-indic
The following NEW packages will be installed:
ca-certificates-java daemon default-jre-headless java-common jenkins
openjdk-8-jre-headless
0 upgraded, 6 newly installed, 0 to remove and 0 not upgraded.
Need to get 101 MB of archives.
After this operation, 174 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu xenial/main amd64 java-common all 0.56ubuntu2 [7,742 B]
Get:2 http://archive.ubuntu.com/ubuntu xenial/main amd64 default-jre-headless amd64 2:1.8-56ubuntu2 [4,380 B]
Get:3 http://archive.ubuntu.com/ubuntu xenial/main amd64 ca-certificates-java all 20160321 [12.9 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial/main amd64 openjdk-8-jre-headless amd64 8u77-b03-3ubuntu3 [26.9 MB]
Get:5 https://pkg.jenkins.io/debian-stable binary/ jenkins 2.89.4 [73.7 MB]
Get:6 http://archive.ubuntu.com/ubuntu xenial/universe amd64 daemon amd64 0.6.4-1 [98.2 kB]
Fetched 101 MB in 2min 9s (775 kB/s)
Selecting previously unselected package java-common.
(Reading database … 217445 files and directories currently installed.)
Preparing to unpack …/java-common_0.56ubuntu2_all.deb …
Unpacking java-common (0.56ubuntu2) …
Selecting previously unselected package default-jre-headless.
Preparing to unpack …/default-jre-headless_2%3a1.8-56ubuntu2_amd64.deb …
Unpacking default-jre-headless (2:1.8-56ubuntu2) …
Selecting previously unselected package ca-certificates-java.
Preparing to unpack …/ca-certificates-java_20160321_all.deb …
Unpacking ca-certificates-java (20160321) …
Selecting previously unselected package openjdk-8-jre-headless:amd64.
Preparing to unpack …/openjdk-8-jre-headless_8u77-b03-3ubuntu3_amd64.deb …
Unpacking openjdk-8-jre-headless:amd64 (8u77-b03-3ubuntu3) …
Selecting previously unselected package daemon.
Preparing to unpack …/daemon_0.6.4-1_amd64.deb …
Unpacking daemon (0.6.4-1) …
Selecting previously unselected package jenkins.
Preparing to unpack …/jenkins_2.89.4_all.deb …
Unpacking jenkins (2.89.4) …
Processing triggers for man-db (2.7.5-1) …
Processing triggers for ca-certificates (20170717~16.04.1) …
Updating certificates in /etc/ssl/certs…
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d…
done.
Processing triggers for systemd (229-4ubuntu21.1) …
Processing triggers for ureadahead (0.100.0-19) …
Setting up java-common (0.56ubuntu2) …
Setting up daemon (0.6.4-1) …
Setting up openjdk-8-jre-headless:amd64 (8u77-b03-3ubuntu3) …
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/rmid to provide /usr/bin/rmid (rmid) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java to provide /usr/bin/java (java) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/keytool to provide /usr/bin/keytool (keytool) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/jjs to provide /usr/bin/jjs (jjs) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/pack200 to provide /usr/bin/pack200 (pack200) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/rmiregistry to provide /usr/bin/rmiregistry (rmiregistry) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/unpack200 to provide /usr/bin/unpack200 (unpack200) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/orbd to provide /usr/bin/orbd (orbd) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/servertool to provide /usr/bin/servertool (servertool) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/tnameserv to provide /usr/bin/tnameserv (tnameserv) in auto mode
update-alternatives: using /usr/lib/jvm/java-8-openjdk-amd64/jre/lib/jexec to provide /usr/bin/jexec (jexec) in auto mode
Setting up ca-certificates-java (20160321) …
Adding debian:Chambers_of_Commerce_Root_-_2008.pem
Adding debian:GeoTrust_Primary_Certification_Authority_-_G3.pem
Adding debian:OISTE_WISeKey_Global_Root_GA_CA.pem
Adding debian:Deutsche_Telekom_Root_CA_2.pem
Adding debian:Izenpe.com.pem
Adding debian:Microsec_e-Szigno_Root_CA_2009.pem
Adding debian:EC-ACC.pem
Adding debian:DigiCert_Global_Root_G2.pem
Adding debian:QuoVadis_Root_CA_3.pem
Adding debian:ePKI_Root_Certification_Authority.pem
Adding debian:GeoTrust_Primary_Certification_Authority_-_G2.pem
Adding debian:Autoridad_de_Certificacion_Firmaprofesional_CIF_A62634068.pem
Adding debian:ACCVRAIZ1.pem
Adding debian:Cybertrust_Global_Root.pem
Adding debian:COMODO_ECC_Certification_Authority.pem
Adding debian:GeoTrust_Universal_CA_2.pem
Adding debian:Entrust_Root_Certification_Authority_-_EC1.pem
Adding debian:Sonera_Class_2_Root_CA.pem
Adding debian:Comodo_AAA_Services_root.pem
Adding debian:Security_Communication_EV_RootCA1.pem
Adding debian:AddTrust_Low-Value_Services_Root.pem
Adding debian:Amazon_Root_CA_1.pem
Adding debian:DST_Root_CA_X3.pem
Adding debian:OpenTrust_Root_CA_G1.pem
Adding debian:T-TeleSec_GlobalRoot_Class_3.pem
Adding debian:Camerfirma_Chambers_of_Commerce_Root.pem
Adding debian:Atos_TrustedRoot_2011.pem
Adding debian:Starfield_Class_2_CA.pem
Adding debian:Certigna.pem
Adding debian:Buypass_Class_3_Root_CA.pem
Adding debian:COMODO_Certification_Authority.pem
Adding debian:thawte_Primary_Root_CA_-_G3.pem
Adding debian:Swisscom_Root_EV_CA_2.pem
Adding debian:Go_Daddy_Class_2_CA.pem
Adding debian:VeriSign_Universal_Root_Certification_Authority.pem
Adding debian:Global_Chambersign_Root_-_2008.pem
Adding debian:CNNIC_ROOT.pem
Adding debian:AddTrust_External_Root.pem
Adding debian:SwissSign_Gold_CA_-_G2.pem
Adding debian:QuoVadis_Root_CA_1_G3.pem
Adding debian:GeoTrust_Primary_Certification_Authority.pem
Adding debian:Hongkong_Post_Root_CA_1.pem
Adding debian:TWCA_Global_Root_CA.pem
Adding debian:ACEDICOM_Root.pem
Adding debian:Go_Daddy_Root_Certificate_Authority_-_G2.pem
Adding debian:Staat_der_Nederlanden_EV_Root_CA.pem
Adding debian:GlobalSign_ECC_Root_CA_-_R4.pem
Adding debian:Entrust_Root_Certification_Authority_-_G2.pem
Adding debian:Taiwan_GRCA.pem
Adding debian:Verisign_Class_3_Public_Primary_Certification_Authority_-_G3.pem
Adding debian:COMODO_RSA_Certification_Authority.pem
Adding debian:ssl-cert-snakeoil.pem
Adding debian:DigiCert_High_Assurance_EV_Root_CA.pem
Adding debian:GeoTrust_Global_CA.pem
Adding debian:Security_Communication_RootCA2.pem
Adding debian:QuoVadis_Root_CA.pem
Adding debian:D-TRUST_Root_Class_3_CA_2_2009.pem
Adding debian:D-TRUST_Root_Class_3_CA_2_EV_2009.pem
Adding debian:UTN_USERFirst_Hardware_Root_CA.pem
Adding debian:DST_ACES_CA_X6.pem
Adding debian:Visa_eCommerce_Root.pem
Adding debian:Certinomis_-_Autorité_Racine.pem
Adding debian:thawte_Primary_Root_CA_-_G2.pem
Adding debian:Staat_der_Nederlanden_Root_CA_-_G2.pem
Adding debian:E-Tugra_Certification_Authority.pem
Adding debian:QuoVadis_Root_CA_2_G3.pem
Adding debian:Entrust.net_Premium_2048_Secure_Server_CA.pem
Adding debian:TURKTRUST_Certificate_Services_Provider_Root_2007.pem
Adding debian:SwissSign_Silver_CA_-_G2.pem
Adding debian:TWCA_Root_Certification_Authority.pem
Adding debian:Certum_Trusted_Network_CA_2.pem
Adding debian:T-TeleSec_GlobalRoot_Class_2.pem
Adding debian:GlobalSign_Root_CA_-_R2.pem
Adding debian:LuxTrust_Global_Root_2.pem
Adding debian:AddTrust_Public_Services_Root.pem
Adding debian:Staat_der_Nederlanden_Root_CA_-_G3.pem
Adding debian:USERTrust_ECC_Certification_Authority.pem
Adding debian:AffirmTrust_Networking.pem
Adding debian:Amazon_Root_CA_4.pem
Adding debian:Starfield_Services_Root_Certificate_Authority_-_G2.pem
Adding debian:TÜRKTRUST_Elektronik_Sertifika_Hizmet_Saglayicisi_H5.pem
Adding debian:ISRG_Root_X1.pem
Adding debian:AC_RAIZ_FNMT-RCM.pem
Adding debian:Swisscom_Root_CA_2.pem
Adding debian:DigiCert_Trusted_Root_G4.pem
Adding debian:GlobalSign_Root_CA.pem
Adding debian:CA_Disig_Root_R2.pem
Adding debian:OISTE_WISeKey_Global_Root_GB_CA.pem
Adding debian:TeliaSonera_Root_CA_v1.pem
Adding debian:Comodo_Trusted_Services_root.pem
Adding debian:Certum_Trusted_Network_CA.pem
Adding debian:NetLock_Arany_=Class_Gold=_Fotanúsítvány.pem
Adding debian:AffirmTrust_Premium.pem
Adding debian:AffirmTrust_Premium_ECC.pem
Adding debian:VeriSign_Class_3_Public_Primary_Certification_Authority_-_G5.pem
Adding debian:Secure_Global_CA.pem
Adding debian:Certinomis_-_Root_CA.pem
Adding debian:AddTrust_Qualified_Certificates_Root.pem
Adding debian:Certplus_Root_CA_G2.pem
Adding debian:Amazon_Root_CA_2.pem
Adding debian:Security_Communication_Root_CA.pem
Adding debian:GeoTrust_Global_CA_2.pem
Adding debian:DigiCert_Global_Root_CA.pem
Adding debian:Starfield_Root_Certificate_Authority_-_G2.pem
Adding debian:IdenTrust_Public_Sector_Root_CA_1.pem
Adding debian:VeriSign_Class_3_Public_Primary_Certification_Authority_-_G4.pem
Adding debian:SZAFIR_ROOT_CA2.pem
Adding debian:PSCProcert.pem
Adding debian:AffirmTrust_Commercial.pem
Adding debian:certSIGN_ROOT_CA.pem
Adding debian:Swisscom_Root_CA_1.pem
Adding debian:Hellenic_Academic_and_Research_Institutions_ECC_RootCA_2015.pem
Adding debian:Certplus_Class_2_Primary_CA.pem
Adding debian:XRamp_Global_CA_Root.pem
Adding debian:GeoTrust_Universal_CA.pem
Adding debian:QuoVadis_Root_CA_3_G3.pem
Adding debian:QuoVadis_Root_CA_2.pem
Adding debian:China_Internet_Network_Information_Center_EV_Certificates_Root.pem
Adding debian:CFCA_EV_ROOT.pem
Adding debian:OpenTrust_Root_CA_G2.pem
Adding debian:Network_Solutions_Certificate_Authority.pem
Adding debian:Amazon_Root_CA_3.pem
Adding debian:Certum_Root_CA.pem
Adding debian:EE_Certification_Centre_Root_CA.pem
Adding debian:Actalis_Authentication_Root_CA.pem
Adding debian:Hellenic_Academic_and_Research_Institutions_RootCA_2015.pem
Adding debian:DigiCert_Assured_ID_Root_G3.pem
Adding debian:SecureTrust_CA.pem
Adding debian:Entrust_Root_Certification_Authority.pem
Adding debian:DigiCert_Assured_ID_Root_G2.pem
Adding debian:Certplus_Root_CA_G1.pem
Adding debian:TUBITAK_Kamu_SM_SSL_Kok_Sertifikasi_-_Surum_1.pem
Adding debian:TÜBITAK_UEKAE_Kök_Sertifika_Hizmet_Saglayicisi_-_Sürüm_3.pem
Adding debian:GlobalSign_Root_CA_-_R3.pem
Adding debian:IdenTrust_Commercial_Root_CA_1.pem
Adding debian:OpenTrust_Root_CA_G3.pem
Adding debian:thawte_Primary_Root_CA.pem
Adding debian:USERTrust_RSA_Certification_Authority.pem
Adding debian:DigiCert_Assured_ID_Root_CA.pem
Adding debian:Buypass_Class_2_Root_CA.pem
Adding debian:CA_Disig_Root_R1.pem
Adding debian:Trustis_FPS_Root_CA.pem
Adding debian:Baltimore_CyberTrust_Root.pem
Adding debian:GlobalSign_ECC_Root_CA_-_R5.pem
Adding debian:Comodo_Secure_Services_root.pem
Adding debian:DigiCert_Global_Root_G3.pem
Adding debian:Hellenic_Academic_and_Research_Institutions_RootCA_2011.pem
Adding debian:Camerfirma_Global_Chambersign_Root.pem
Adding debian:SecureSign_RootCA11.pem
done.
Setting up default-jre-headless (2:1.8-56ubuntu2) …
Setting up jenkins (2.89.4) …
Processing triggers for ca-certificates (20170717~16.04.1) …
Updating certificates in /etc/ssl/certs…
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d…

done.
done.
Processing triggers for systemd (229-4ubuntu21.1) …
Processing triggers for ureadahead (0.100.0-19) …
vskumar@ubuntu:~$
== End of Jenkins intallation ========>

==== Updates ====>

vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt-get update
Hit:1 http://ppa.launchpad.net/webupd8team/java/ubuntu xenial InRelease
Hit:2 http://archive.ubuntu.com/ubuntu xenial InRelease
Hit:3 https://download.docker.com/linux/ubuntu xenial InRelease
Ign:4 https://pkg.jenkins.io/debian-stable binary/ InRelease
Hit:5 https://pkg.jenkins.io/debian-stable binary/ Release
Reading package lists… Done
vskumar@ubuntu:~$
=============>

Step5:

How to install apache2?:
If we need to use jenkins apache2 is required.
Now let us install apache2

=== Output for apache installation ===>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo apt install apache2
Reading package lists… Done
Building dependency tree
Reading state information… Done
The following additional packages will be installed:
apache2-bin apache2-data apache2-utils libapr1 libaprutil1
libaprutil1-dbd-sqlite3 libaprutil1-ldap liblua5.1-0
Suggested packages:
apache2-doc apache2-suexec-pristine | apache2-suexec-custom
The following NEW packages will be installed:
apache2 apache2-bin apache2-data apache2-utils libapr1 libaprutil1
libaprutil1-dbd-sqlite3 libaprutil1-ldap liblua5.1-0
0 upgraded, 9 newly installed, 0 to remove and 0 not upgraded.
Need to get 1,532 kB of archives.
After this operation, 6,350 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu xenial/main amd64 libapr1 amd64 1.5.2-3 [86.0 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial/main amd64 libaprutil1 amd64 1.5.4-1build1 [77.1 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial/main amd64 libaprutil1-dbd-sqlite3 amd64 1.5.4-1build1 [10.6 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial/main amd64 libaprutil1-ldap amd64 1.5.4-1build1 [8,720 B]
Get:5 http://archive.ubuntu.com/ubuntu xenial/main amd64 liblua5.1-0 amd64 5.1.5-8ubuntu1 [102 kB]
Get:6 http://archive.ubuntu.com/ubuntu xenial/main amd64 apache2-bin amd64 2.4.18-2ubuntu3 [918 kB]
Get:7 http://archive.ubuntu.com/ubuntu xenial/main amd64 apache2-utils amd64 2.4.18-2ubuntu3 [81.1 kB]
Get:8 http://archive.ubuntu.com/ubuntu xenial/main amd64 apache2-data all 2.4.18-2ubuntu3 [162 kB]
Get:9 http://archive.ubuntu.com/ubuntu xenial/main amd64 apache2 amd64 2.4.18-2ubuntu3 [86.6 kB]
Fetched 1,532 kB in 5s (270 kB/s)
Selecting previously unselected package libapr1:amd64.
(Reading database … 217703 files and directories currently installed.)
Preparing to unpack …/libapr1_1.5.2-3_amd64.deb …
Unpacking libapr1:amd64 (1.5.2-3) …
Selecting previously unselected package libaprutil1:amd64.
Preparing to unpack …/libaprutil1_1.5.4-1build1_amd64.deb …
Unpacking libaprutil1:amd64 (1.5.4-1build1) …
Selecting previously unselected package libaprutil1-dbd-sqlite3:amd64.
Preparing to unpack …/libaprutil1-dbd-sqlite3_1.5.4-1build1_amd64.deb …
Unpacking libaprutil1-dbd-sqlite3:amd64 (1.5.4-1build1) …
Selecting previously unselected package libaprutil1-ldap:amd64.
Preparing to unpack …/libaprutil1-ldap_1.5.4-1build1_amd64.deb …
Unpacking libaprutil1-ldap:amd64 (1.5.4-1build1) …
Selecting previously unselected package liblua5.1-0:amd64.
Preparing to unpack …/liblua5.1-0_5.1.5-8ubuntu1_amd64.deb …
Unpacking liblua5.1-0:amd64 (5.1.5-8ubuntu1) …
Selecting previously unselected package apache2-bin.
Preparing to unpack …/apache2-bin_2.4.18-2ubuntu3_amd64.deb …
Unpacking apache2-bin (2.4.18-2ubuntu3) …
Selecting previously unselected package apache2-utils.
Preparing to unpack …/apache2-utils_2.4.18-2ubuntu3_amd64.deb …
Unpacking apache2-utils (2.4.18-2ubuntu3) …
Selecting previously unselected package apache2-data.
Preparing to unpack …/apache2-data_2.4.18-2ubuntu3_all.deb …
Unpacking apache2-data (2.4.18-2ubuntu3) …
Selecting previously unselected package apache2.
Preparing to unpack …/apache2_2.4.18-2ubuntu3_amd64.deb …
Unpacking apache2 (2.4.18-2ubuntu3) …
Processing triggers for libc-bin (2.23-0ubuntu10) …
Processing triggers for man-db (2.7.5-1) …
Processing triggers for systemd (229-4ubuntu21.1) …
Processing triggers for ureadahead (0.100.0-19) …
Processing triggers for ufw (0.35-0ubuntu2) …
Setting up libapr1:amd64 (1.5.2-3) …
Setting up libaprutil1:amd64 (1.5.4-1build1) …
Setting up libaprutil1-dbd-sqlite3:amd64 (1.5.4-1build1) …
Setting up libaprutil1-ldap:amd64 (1.5.4-1build1) …
Setting up liblua5.1-0:amd64 (5.1.5-8ubuntu1) …
Setting up apache2-bin (2.4.18-2ubuntu3) …
Setting up apache2-utils (2.4.18-2ubuntu3) …
Setting up apache2-data (2.4.18-2ubuntu3) …
Setting up apache2 (2.4.18-2ubuntu3) …
Enabling module mpm_event.
Enabling module authz_core.
Enabling module authz_host.
Enabling module authn_core.
Enabling module auth_basic.
Enabling module access_compat.
Enabling module authn_file.
Enabling module authz_user.
Enabling module alias.
Enabling module dir.
Enabling module autoindex.
Enabling module env.
Enabling module mime.
Enabling module negotiation.
Enabling module setenvif.
Enabling module filter.
Enabling module deflate.
Enabling module status.
Enabling conf charset.
Enabling conf localized-error-pages.
Enabling conf other-vhosts-access-log.
Enabling conf security.
Enabling conf serve-cgi-bin.
Enabling site 000-default.
Processing triggers for libc-bin (2.23-0ubuntu10) …
Processing triggers for systemd (229-4ubuntu21.1) …
Processing triggers for ureadahead (0.100.0-19) …
Processing triggers for ufw (0.35-0ubuntu2) …
vskumar@ubuntu:~$
=== Apaches is installed ===>

Let us check its status:

== Status of apache2 ===>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ service status apache2
status: unrecognized service
vskumar@ubuntu:~$ service apache2 status
? apache2.service – LSB: Apache2 web server
Loaded: loaded (/etc/init.d/apache2; bad; vendor preset: enabled)
Drop-In: /lib/systemd/system/apache2.service.d
+-apache2-systemd.conf
Active: active (running) since Thu 2018-02-22 02:30:24 PST; 1min 6s ago
Docs: man:systemd-sysv-generator(8)
CGroup: /system.slice/apache2.service
+-12680 /usr/sbin/apache2 -k start
+-12683 /usr/sbin/apache2 -k start
+-12684 /usr/sbin/apache2 -k start

Feb 22 02:30:22 ubuntu systemd[1]: Starting LSB: Apache2 web server…
Feb 22 02:30:22 ubuntu apache2[12651]: * Starting Apache httpd web server apach
Feb 22 02:30:23 ubuntu apache2[12651]: AH00558: apache2: Could not reliably dete
Feb 22 02:30:24 ubuntu apache2[12651]: *
Feb 22 02:30:24 ubuntu systemd[1]: Started LSB: Apache2 web server.
lines 1-16/16 (END)
================>

Now, let us check the status for Jenkins:

===== Jenkins status ===>

vskumar@ubuntu:~$ service jenkins status
? jenkins.service – LSB: Start Jenkins at boot time
Loaded: loaded (/etc/init.d/jenkins; bad; vendor preset: enabled)
Active: active (exited) since Thu 2018-02-22 02:13:57 PST; 23min ago
Docs: man:systemd-sysv-generator(8)

Feb 22 02:13:51 ubuntu systemd[1]: Starting LSB: Start Jenkins at boot time…
Feb 22 02:13:51 ubuntu jenkins[10140]: * Starting Jenkins Automation Server jen
Feb 22 02:13:52 ubuntu su[10168]: Successful su for jenkins by root
Feb 22 02:13:52 ubuntu su[10168]: + ??? root:jenkins
Feb 22 02:13:52 ubuntu su[10168]: pam_unix(su:session): session opened for user
Feb 22 02:13:57 ubuntu jenkins[10140]: …done.
Feb 22 02:13:57 ubuntu systemd[1]: Started LSB: Start Jenkins at boot time.
lines 1-12/12 (END)
==== Jenkins is running ======>

How to check on browser in Ubuntu for Jenkins web page ?:

You can also check the ubuntu browser with the below
url:http://localhost:8080/login?from=%2F
There should be a web page displayed with the message:
“Unlock Jenkins”.

It means Jenkins is available to use.

Step6:
Now, we need to setup the admin password.
Read the content on the web page.
You are advised to use the initial password from:
/var/lib/jenkins/secrets/initialAdminPassword

Let us go to that directory to get copy and paste it on
web page.

In my case I got the below:
==== PWD display ===>
vskumar@ubuntu:~$ sudo cat /var/lib/jenkins/secrets/initialAdminPassword
711a4d7d01244651a490cfd4a61439e2
vskumar@ubuntu:~$
========>

I have pasted it on web page.
Till you change the pwd, this will be the default one.

==== List of the files in jenkins dir ===>
vskumar@ubuntu:/var/lib/jenkins$ ls -l
total 60
-rw-r–r– 1 jenkins jenkins 1820 Feb 22 02:17 config.xml
-rw-r–r– 1 jenkins jenkins 156 Feb 22 02:15 hudson.model.UpdateCenter.xml
-rw——- 1 jenkins jenkins 1712 Feb 22 02:15 identity.key.enc
-rw-r–r– 1 jenkins jenkins 94 Feb 22 02:16 jenkins.CLI.xml
-rw-r–r– 1 jenkins jenkins 6 Feb 22 02:16 jenkins.install.UpgradeWizard.state
drwxr-xr-x 2 jenkins jenkins 4096 Feb 22 02:15 jobs
drwxr-xr-x 3 jenkins jenkins 4096 Feb 22 02:16 logs
-rw-r–r– 1 jenkins jenkins 907 Feb 22 02:16 nodeMonitors.xml
drwxr-xr-x 2 jenkins jenkins 4096 Feb 22 02:15 nodes
drwxr-xr-x 2 jenkins jenkins 4096 Feb 22 02:15 plugins
-rw-r–r– 1 jenkins jenkins 64 Feb 22 02:15 secret.key
-rw-r–r– 1 jenkins jenkins 0 Feb 22 02:15 secret.key.not-so-secret
drwx—— 4 jenkins jenkins 4096 Feb 22 02:16 secrets
drwxr-xr-x 2 jenkins jenkins 4096 Feb 22 02:18 updates
drwxr-xr-x 2 jenkins jenkins 4096 Feb 22 02:16 userContent
drwxr-xr-x 3 jenkins jenkins 4096 Feb 22 02:16 users
vskumar@ubuntu:/var/lib/jenkins$ cd jobs
vskumar@ubuntu:/var/lib/jenkins/jobs$ ls
vskumar@ubuntu:/var/lib/jenkins/jobs$ pwd
/var/lib/jenkins/jobs
vskumar@ubuntu:/var/lib/jenkins/jobs$
==================>
We need to remember the above directories.

By default we can install ‘suggested plugins’ for now.
It shows the plugins updates.
Once they are installed, you will be prompted for a uid/pwd/name/e-mail.
You can fill them, and start using jenkins.

That is all the installation of Jenkins 2.9.

This video is made to motivate the new DevOps engineers to learn and do a kind of trouble shooting, while doing Jenkins installation on a Virtual machine of Ubuntu.

To try one job build you can go through my another blog:

https://vskumar.blog/2017/11/26/2-devops-jenkins2-9-how-to-create-and-build-the-job/

Good luck!! and you can start practicing Jenkins. 

Please leave your feedback!!

Vcard-Shanthi Kumar V-v3

12. DevOps: How to build docker images using dockerfile ? -1

 

Docker-logo

In continuation of my  previous session on :”11. DevOps: How to Launch a container as a daemon ?”, in this session I would like to demonstrate the exercises on:

“How to build docker images using dockerfile ?:”

These images are basic operating environments, such as ubuntu.
We found these while doing the other lab exercises.
The docker images can craft advanced application stacks for the enterprise and cloud IT environments.
Currently let us craft an image manually by launching a container from a base image.
A best practices is, we can build an automated approach of crafting the images using Dockerfile.
The dockerfile is a a text-based build script which contains special instructions in a sequence for building the correct and the relevant images from the base images.

Please note; we will explore all these combinations in different sessions.

Now, let us understand this automated approach from the below steps:
1. The sequential instructions inside Dockerfile can include selecting the base image as 1st statement.
2. And in the later statements; installing the required application, adding the configuration and the data files, and automatically running the services as well as exposing those services to the external world.

This way the dockerfile based automated build approach has simplified the image building process.

It also offers a great deal of flexibility in organizing the build instructions and in visualizing the complete build process, while running the script instructions.

The Docker Engine tightly integrates this build process with the help of the docker ‘build’ subcommand.

This process involes the below steps:
1. Let us imagine; in the client server scenario of Docker, the Docker server (or daemon) is responsible towards complete build process.
2. And the Docker command-line interface is responsible for transferring the build context, including transferring Dockerfile to the daemon.
Now, let us list our existing images as below, in continuation of previous exercise:
=============>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
busybox latest 6ad733544a63 4 weeks ago 1.13MB
busybox 1.24 47bcc53f74dc 20 months ago 1.11MB
vskumar@ubuntu:~$
====================>
Now,  let us create a simple container from the ubuntu base image.
To create it, we can create ‘dockerfile’ without extension using vi in the current pwd.

Please note we do not have vim utility in this Ubuntu base image.
=================>
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ vi dockerfile
============>
Now, let us cat the dockerfile as below:
=============>
vskumar@ubuntu:~$ ls -l
total 48
drwxr-xr-x 3 vskumar vskumar 4096 Nov 24 23:32 Desktop
-rw-rw-r– 1 vskumar vskumar 86 Dec 3 04:29 dockerfile
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 21:23 Documents
drwxr-xr-x 2 vskumar vskumar 4096 Nov 25 06:33 Downloads
-rw-r–r– 1 vskumar vskumar 8980 Nov 22 21:03 examples.desktop
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 21:23 Music
drwxr-xr-x 2 vskumar vskumar 4096 Nov 25 06:02 Pictures
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 21:23 Public
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 21:23 Templates
drwxr-xr-x 2 vskumar vskumar 4096 Nov 22 21:23 Videos
vskumar@ubuntu:~$
vskumar@ubuntu:~$ cat dockerfile
FROM ubuntu
CMD [“echo”, “This is done by vskumar for a lab practice of dockerfile”]
vskumar@ubuntu:~$
================>
From the above dockerfile contents:
1st line FROM ubuntu – denotes it is using the buntu as the base image to create the container.
2nd line: CMD [“echo”, “This is done by vskumar for a lab practice of dockerfile”]
denotes using CMD echo command is executed to print the message “This is done by vskumar for a lab practice of dockerfile”.
Now let us run this file through the below command:
$ sudo docker build .
We can see the output as below:
===============>
vskumar@ubuntu:~$ sudo docker build .
Sending build context to Docker daemon 112MB
Step 1/2 : FROM ubuntu
—> 20c44cd7596f
Step 2/2 : CMD [“echo”, “This is done by vskumar for a lab practice of dockerfile”]
—> Running in 1de59a4799fa
Removing intermediate container 1de59a4799fa
—> 8de083612fef
Successfully built 8de083612fef
vskumar@ubuntu:~$
===================>
Now, let us list the images:
==================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
<none> <none> 8de083612fef About a minute ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
busybox latest 6ad733544a63 4 weeks ago 1.13MB
busybox 1.24 47bcc53f74dc 20 months ago 1.11MB
vskumar@ubuntu:~$
==========================>
We can see Imgae id: 8de083612fef is created just now.
Look into that line there is no tag given.
Now let us tag it as below:
$ sudo docker tag 8de083612fef ubuntu-testbox1
================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo docker tag 8de083612fef ubuntu-testbox1
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-testbox1 latest 8de083612fef 4 minutes ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
busybox latest 6ad733544a63 4 weeks ago 1.13MB
busybox 1.24 47bcc53f74dc 20 months ago 1.11MB
vskumar@ubuntu:~$
====================>
Now, let us do some housekeeping on these containers.
Let us list the containers using ps -a command
====================>
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
0fe495fc93ed ubuntu “/bin/bash -c ‘while…” 8 hours ago Exited (137) 4 hours ago hungry_engelbart
10ffea6140f9 ubuntu “bash” 7 days ago Exited (0) 7 days ago quizzical_lalande
b2a79f8d2fe6 ubuntu “/bin/bash -c ‘while…” 7 days ago Exited (255) 7 days ago goofy_borg
155f4b0764b1 ubuntu:16.04 “/bin/bash” 7 days ago Exited (0) 7 days ago zen_volhard
vskumar@ubuntu:~$
=====================>
I want to remove all of them. We can recreate with the dockerfile as an exercise.
$ Sudo docker containers prune
=======================================>
vskumar@ubuntu:~$ sudo docker ps -aq
0fe495fc93ed
10ffea6140f9
b2a79f8d2fe6
155f4b0764b1
vskumar@ubuntu:~$ sudo docker container prune
WARNING! This will remove all stopped containers.
Are you sure you want to continue? [y/N] y
Deleted Containers:
0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd
10ffea6140f9c93b37bad2f9d159ad53aa121c0de69a9d145f07cc12f9591324
b2a79f8d2fe65453fce19f00d7adf03ed6dcced69ae68fba94ad0c416545263e
155f4b0764b16f1c8776a101cced6ea95c55eeabe69aeab8520cbe925bedc456

Total reclaimed space: 186B
vskumar@ubuntu:~$ sudo docker ps -aq
vskumar@ubuntu:~$
============== so now there are no containers =========>
Let us build the container.
Before building let us check the available images:
==================>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-testbox1 latest 8de083612fef 24 minutes ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
busybox latest 6ad733544a63 4 weeks ago 1.13MB
busybox 1.24 47bcc53f74dc 20 months ago 1.11MB
vskumar@ubuntu:~$
====================>
Let us remove some more images also.
We need to use the below commands:
=========== Let us try one image removal =========>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-testbox1 latest 8de083612fef 33 minutes ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
busybox latest 6ad733544a63 4 weeks ago 1.13MB
busybox 1.24 47bcc53f74dc 20 months ago 1.11MB
vskumar@ubuntu:~$ sudo docker rmi image 47bcc53f74dc
Untagged: busybox:1.24
Untagged: busybox@sha256:8ea3273d79b47a8b6d018be398c17590a4b5ec604515f416c5b797db9dde3ad8
Deleted: sha256:47bcc53f74dc94b1920f0b34f6036096526296767650f223433fe65c35f149eb
Deleted: sha256:f6075681a244e9df4ab126bce921292673c9f37f71b20f6be1dd3bb99b4fdd72
Deleted: sha256:1834950e52ce4d5a88a1bbd131c537f4d0e56d10ff0dd69e66be3b7dfa9df7e6
Error: No such image: image
vskumar@ubuntu:~$
=================================>
So, by using :
sudo docker rmi image [image id], we can remove the image.

Now, further continuation of our dockerfile exercise;
We can create a container from ubuntu base image and install vim package on it with the help of dockerfile.
To do this we need to have following dockerfile script.
——————>
FROM ubuntu
RUN apt-get update
RUN apt-get -y install vim
CMD [“echo”, “This is done by vskumar for a lab demo on dockerfile”]
—————–>
Before doing it, let me do some housekeeping.
I have removed the below image:
==================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ sudo docker rmi image 6ad733544a63
Untagged: busybox:latest
Untagged: busybox@sha256:bbc3a03235220b170ba48a157dd097dd1379299370e1ed99ce976df0355d24f0
Deleted: sha256:6ad733544a6317992a6fac4eb19fe1df577d4dec7529efec28a5bd0edad0fd30
Deleted: sha256:0271b8eebde3fa9a6126b1f2335e170f902731ab4942f9f1914e77016540c7bb
Error: No such image: image
=====================>
See the current status:
===================>
vskumar@ubuntu:~$ ls
Desktop dockerfile Documents Downloads examples.desktop Music Pictures Public Templates Videos
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-testbox1 latest 8de083612fef About an hour ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$
======================>
Now let me update the dockerfile through vi and cat that file:
====================>
vskumar@ubuntu:~$
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ vi dockerfile
vskumar@ubuntu:~$ cat dockerfile
FROM ubuntu
RUN apt-get update
RUN apt-get -y install vim
CMD [“echo”, “This is done by vskumar for a lab practice of dockerfile”]
vskumar@ubuntu:~$
====================>
Now let me run the below command:
$ sudo docker build -t ubuntu-vmbox .
This time; I have added the tag name as ‘ ubuntu-vmbox’.
We need to understand; there are below tasks it involves:
1. Updating the ubuntu libraries – it takes some time by displaying lot of output.
2. Installing vim utility. — This also takes some time.
3. Displaying the message.
We can see this large size output:
=========== Update the packages and install the vim in a conatiner ==========>
vskumar@ubuntu:~$ pwd
/home/vskumar
vskumar@ubuntu:~$ sudo docker build -t ubuntu-vmbox .
Sending build context to Docker daemon 112MB
Step 1/4 : FROM ubuntu
latest: Pulling from library/ubuntu
Digest: sha256:7c67a2206d3c04703e5c23518707bdd4916c057562dd51c74b99b2ba26af0f79
Status: Downloaded newer image for ubuntu:latest
—> 20c44cd7596f
Step 2/4 : RUN apt-get update
—> Running in df81eaef9437
Get:1 http://archive.ubuntu.com/ubuntu xenial InRelease [247 kB]
Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
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Get:7 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages [1558 kB]
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Get:21 http://security.ubuntu.com/ubuntu xenial-security/multiverse amd64 Packages [3479 B]
Fetched 24.6 MB in 2min 5s (196 kB/s)
Reading package lists…
Removing intermediate container df81eaef9437
—> 13cd766374bc
Step 3/4 : RUN apt-get -y install vim
—> Running in d37783a8cb7d
Reading package lists…
Building dependency tree…
Reading state information…
The following additional packages will be installed:
file libexpat1 libgpm2 libmagic1 libmpdec2 libpython3.5 libpython3.5-minimal
libpython3.5-stdlib libsqlite3-0 libssl1.0.0 mime-support vim-common
vim-runtime
Suggested packages:
gpm ctags vim-doc vim-scripts vim-gnome-py2 | vim-gtk-py2 | vim-gtk3-py2
| vim-athena-py2 | vim-nox-py2
The following NEW packages will be installed:
file libexpat1 libgpm2 libmagic1 libmpdec2 libpython3.5 libpython3.5-minimal
libpython3.5-stdlib libsqlite3-0 libssl1.0.0 mime-support vim vim-common
vim-runtime
0 upgraded, 14 newly installed, 0 to remove and 2 not upgraded.
Need to get 12.2 MB of archives.
After this operation, 58.3 MB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu xenial/main amd64 libgpm2 amd64 1.20.4-6.1 [16.5 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial/main amd64 libmagic1 amd64 1:5.25-2ubuntu1 [216 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial/main amd64 file amd64 1:5.25-2ubuntu1 [21.2 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libexpat1 amd64 2.1.0-7ubuntu0.16.04.3 [71.2 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial/main amd64 libmpdec2 amd64 2.4.2-1 [82.6 kB]
Get:6 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libssl1.0.0 amd64 1.0.2g-1ubuntu4.9 [1085 kB]
Get:7 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libpython3.5-minimal amd64 3.5.2-2ubuntu0~16.04.4 [523 kB]
Get:8 http://archive.ubuntu.com/ubuntu xenial/main amd64 mime-support all 3.59ubuntu1 [31.0 kB]
Get:9 http://archive.ubuntu.com/ubuntu xenial/main amd64 libsqlite3-0 amd64 3.11.0-1ubuntu1 [396 kB]
Get:10 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libpython3.5-stdlib amd64 3.5.2-2ubuntu0~16.04.4 [2132 kB]
Get:11 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 vim-common amd64 2:7.4.1689-3ubuntu1.2 [103 kB]
Get:12 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libpython3.5 amd64 3.5.2-2ubuntu0~16.04.4 [1360 kB]
Get:13 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 vim-runtime all 2:7.4.1689-3ubuntu1.2 [5164 kB]
Get:14 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 vim amd64 2:7.4.1689-3ubuntu1.2 [1036 kB]
debconf: delaying package configuration, since apt-utils is not installed
Fetched 12.2 MB in 12s (949 kB/s)
Selecting previously unselected package libgpm2:amd64.
(Reading database … 4768 files and directories currently installed.)
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Selecting previously unselected package libpython3.5:amd64.
Preparing to unpack …/libpython3.5_3.5.2-2ubuntu0~16.04.4_amd64.deb …
Unpacking libpython3.5:amd64 (3.5.2-2ubuntu0~16.04.4) …
Selecting previously unselected package vim-runtime.
Preparing to unpack …/vim-runtime_2%3a7.4.1689-3ubuntu1.2_all.deb …
Adding ‘diversion of /usr/share/vim/vim74/doc/help.txt to /usr/share/vim/vim74/doc/help.txt.vim-tiny by vim-runtime’
Adding ‘diversion of /usr/share/vim/vim74/doc/tags to /usr/share/vim/vim74/doc/tags.vim-tiny by vim-runtime’
Unpacking vim-runtime (2:7.4.1689-3ubuntu1.2) …
Selecting previously unselected package vim.
Preparing to unpack …/vim_2%3a7.4.1689-3ubuntu1.2_amd64.deb …
Unpacking vim (2:7.4.1689-3ubuntu1.2) …
Processing triggers for libc-bin (2.23-0ubuntu9) …
Setting up libgpm2:amd64 (1.20.4-6.1) …
Setting up libmagic1:amd64 (1:5.25-2ubuntu1) …
Setting up file (1:5.25-2ubuntu1) …
Setting up libexpat1:amd64 (2.1.0-7ubuntu0.16.04.3) …
Setting up libmpdec2:amd64 (2.4.2-1) …
Setting up libssl1.0.0:amd64 (1.0.2g-1ubuntu4.9) …
debconf: unable to initialize frontend: Dialog
debconf: (TERM is not set, so the dialog frontend is not usable.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can’t locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.22.1 /usr/local/share/perl/5.22.1 /usr/lib/x86_64-linux-gnu/perl5/5.22 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.22 /usr/share/perl/5.22 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base .) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Setting up libpython3.5-minimal:amd64 (3.5.2-2ubuntu0~16.04.4) …
Setting up mime-support (3.59ubuntu1) …
Setting up libsqlite3-0:amd64 (3.11.0-1ubuntu1) …
Setting up libpython3.5-stdlib:amd64 (3.5.2-2ubuntu0~16.04.4) …
Setting up vim-common (2:7.4.1689-3ubuntu1.2) …
Setting up libpython3.5:amd64 (3.5.2-2ubuntu0~16.04.4) …
Setting up vim-runtime (2:7.4.1689-3ubuntu1.2) …
Setting up vim (2:7.4.1689-3ubuntu1.2) …
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vim (vim) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vimdiff (vimdiff) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rvim (rvim) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/rview (rview) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/vi (vi) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/view (view) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/ex (ex) in auto mode
update-alternatives: using /usr/bin/vim.basic to provide /usr/bin/editor (editor) in auto mode
Processing triggers for libc-bin (2.23-0ubuntu9) …
Removing intermediate container d37783a8cb7d
—> c07c6f2d2c65
Step 4/4 : CMD [“echo”, “This is done by vskumar for a lab practice of dockerfile”]
—> Running in f7e85f87b578
Removing intermediate container f7e85f87b578
—> f6675f4738b7
Successfully built f6675f4738b7
Successfully tagged ubuntu-vmbox:latest
vskumar@ubuntu:~$
=== Finally you can see the ‘ubuntu-vmbox’ tagged conatiner ======>
We can see the latest image from the below images:
===== Current images list =====>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 3 minutes ago 220MB
ubuntu-testbox1 latest 8de083612fef About an hour ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$
=======================>
Now, I want to work with this newly created container. Please recollect my blog “https://vskumar.blog/2017/11/29/6-devops-how-to-work-with-interactive-docker-containers/”.
As we did practice in it; we can use the below command to work with this new container:

sudo docker run -i -t ubuntu-vmbox /bin/bash
I want to test the vim is working on it. See the below output:
==================>
vskumar@ubuntu:~$ sudo docker run -i -t ubuntu-vmbox /bin/bash

root@1169bb1285cf:/#
root@1169bb1285cf:/# pwd
/
root@1169bb1285cf:/# ls
bin boot dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var
root@1169bb1285cf:/# vim test1
===== I have created the file with vim successfully ====>
Now let me use cat command and see its output:

================>
root@1169bb1285cf:/#
root@1169bb1285cf:/# ls
bin boot dev etc home lib lib64 media mnt opt proc root run sbin srv sys test1 tmp usr var
root@1169bb1285cf:/# cat test1
testing this vim box……
root@1169bb1285cf:/#
=================>

So, in this exercise we have updated the ubuntu libraries and installed vim utility.
And tested the container for vim usage by using interactive mode.

=========== Now let me exit and check the list of images =====>
root@1169bb1285cf:/#
root@1169bb1285cf:/# exit
exit
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 13 minutes ago 220MB
ubuntu-testbox1 latest 8de083612fef About an hour ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$
=============================>
So, the new container ‘ubuntu-vmbox’ is existing.

Now, I want to remove some images:
sudo docker rmi 20c44cd7596f
================>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 18 minutes ago 220MB
ubuntu-testbox1 latest 8de083612fef About an hour ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker rmi 20c44cd7596f
Error response from daemon: conflict: unable to delete 20c44cd7596f (cannot be forced) – image has dependent child images
vskumar@ubuntu:~$
== Please note the last image was the base to build the top tow containers ===>
Hence it has the child and parent relationship.
First we need to remove the child images and later the parent need to be removed.
=== You can see the removal of child one and one more image=====>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 20 minutes ago 220MB
ubuntu-testbox1 latest 8de083612fef 2 hours ago 123MB
docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker rmi 8de083612fef
Untagged: ubuntu-testbox1:latest
Deleted: sha256:8de083612fefbf9723913748f7db4aba4154b17adc500d011f44df356736f06c
vskumar@ubuntu:~$ sudo docker rmi e34304119838
Untagged: docker-exercise/ubuntu-wgetinstall:latest
Deleted: sha256:e34304119838d79da60e12776529106c350b1972cd517648e8ab90311fad7b1a
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 21 minutes ago 220MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$
=================>
Let me do some more exercises on housekeeping.
I would like to present some more dependency issues for the above images. You can clearly see the output:
========= Dependencies =======>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 22 minutes ago 220MB
<none> <none> fc7e4564eb92 7 days ago 169MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker rmi fc7e4564eb92
Deleted: sha256:fc7e4564eb928ccfe068c789f0d650967e8d5dc42d4e8d92409aab6614364075
Deleted: sha256:b16d78406b12e6dbc174f4e71bedb7b9edc0593cad10458ddf042738694c06db
vskumar@ubuntu:~$ sudo docker rmi 20c44cd7596f
Error response from daemon: conflict: unable to delete 20c44cd7596f (cannot be forced) – image has dependent child images
vskumar@ubuntu:~$ sudo docker rmi f6675f4738b7
Error response from daemon: conflict: unable to delete f6675f4738b7 (must be forced) – image is being used by stopped container 1169bb1285cf
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1169bb1285cf ubuntu-vmbox “/bin/bash” 15 minutes ago Exited (0) 11 minutes ago heuristic_mayer
vskumar@ubuntu:~$
====================>
It means the container “1169bb1285cf ubuntu-vmbox” is the child to image id:f6675f4738b7.
===========>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 27 minutes ago 220MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
1169bb1285cf ubuntu-vmbox “/bin/bash” 19 minutes ago Exited (0) 14 minutes ago heuristic_mayer
vskumar@ubuntu:~$
==============>
So if I want to remove Image id: f6675f4738b7, I need to remove the container id:1169bb1285cf , and later I need to remove this image.
$ sudo docker rm container 1169bb1285cf
And later image removal command need to be used as below.
======================>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
ubuntu-vmbox latest f6675f4738b7 31 minutes ago 220MB
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker rmi f6675f4738b7
Untagged: ubuntu-vmbox:latest
Deleted: sha256:f6675f4738b721780721f345906a0c78c13a67ee8239a16f071504b217f41658
Deleted: sha256:c07c6f2d2c651dd406977d42d5504c941d7f975a84c8547abaf3869b50942820
Deleted: sha256:4855cfb7ae6f84279bbbfe87e7691377531a541785c613014f64909e6e0f4528
Deleted: sha256:13cd766374bcb31cc0e8cac971e82754bb8e1bc66780abaff264f847e00a94b2
Deleted: sha256:dc6fab8a33a18a8c840e19612253657c4610ab865a26de5a31260f71bcef5f76
vskumar@ubuntu:~$
========================>
So we have the below images only now:
==== Current images ======>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$
==========================>
We can try to remove the above images:
========= See it is declined due to it is base image ===========>
vskumar@ubuntu:~$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
hello-world latest f2a91732366c 12 days ago 1.85kB
ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB
ubuntu latest 20c44cd7596f 2 weeks ago 123MB
vskumar@ubuntu:~$ sudo docker rmi 20c44cd7596f
Error response from daemon: conflict: unable to delete 20c44cd7596f (must be forced) – image is referenced in multiple repositories
vskumar@ubuntu:~$
=========================>
Both ubuntu images are interlinked and they can not be removed as the base docker engine is working on top of their OS.

We will stop this session at this time.

We will continue some more sessions on “dockerfile”.

 

Vcard-Shanthi Kumar V-v3

11. DevOps: How to Launch a container as a daemon ?

Docker-logo

In continuation of my previous blog on “10. DevOps: How to Build images from Docker containers?”, I am continuing my lab exercises. In this session we can see ”

How to Launch a container as a daemon ?:

Note: If you want to recollect the docker commands to be used during your current lab practice, visit my blog link:

https://vskumarblogs.wordpress.com/2017/12/13/some-useful-docker-commands-for-handling-images-and-containers/

 

Let us recap the past exercises; So far we have experimented with an interactive container, tracked the changes that were made to the containers., created images from the containers, and then gained insights in the containerization scenarios.

Now, let us see the container usage in a detached mode.

When we run the container in a detached mode it runs under a daemon process.

I want to use the “ubuntu” image and run detached mode command.

First, let me check my current docker images:

==================>

vskumar@ubuntu:~$

vskumar@ubuntu:~$ sudo docker images

[sudo] password for vskumar:

REPOSITORY TAG IMAGE ID CREATED SIZE

docker-exercise/ubuntu-wgetinstall latest e34304119838 7 days ago 169MB

<none> <none> fc7e4564eb92 7 days ago 169MB

hello-world latest f2a91732366c 12 days ago 1.85kB

ubuntu 16.04 20c44cd7596f 2 weeks ago 123MB

ubuntu latest 20c44cd7596f 2 weeks ago 123MB

busybox latest 6ad733544a63 4 weeks ago 1.13MB

busybox 1.24 47bcc53f74dc 20 months ago 1.11MB

vskumar@ubuntu:~$

===================>

You can see my previous image with ‘docker-exercise/ubuntu-wgetinstall ‘. This was created in the previous exercise.

As per our plan in this session I am using the below commands to run the ubuntu image as below:

sudo docker run -d ubuntu \

    /bin/bash -c "while true; do date; sleep 5; done";

========== Output ======>
vskumar@ubuntu:~$  sudo docker run -d ubuntu \
>     /bin/bash -c "while true; do date; sleep 5; done";
0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd
vskumar@ubuntu:~$ $ 
=======================>

Now, to view the docker logs I want to run the docker logs subcommand on image id: ‘ 0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd’

$ sudo docker logs 0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd;

=====See the output of the Daemon process running with the ubuntu image ===============>

vskumar@ubuntu:~$ sudo docker logs 0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd;

Sun Dec 3 05:11:57 UTC 2017

Sun Dec 3 05:12:02 UTC 2017

Sun Dec 3 05:12:07 UTC 2017

Sun Dec 3 05:12:12 UTC 2017

Sun Dec 3 05:12:17 UTC 2017

Sun Dec 3 05:12:22 UTC 2017

Sun Dec 3 05:12:27 UTC 2017

Sun Dec 3 05:12:32 UTC 2017

Sun Dec 3 05:12:37 UTC 2017

Sun Dec 3 05:12:42 UTC 2017

Sun Dec 3 05:12:48 UTC 2017

Sun Dec 3 05:12:53 UTC 2017

Sun Dec 3 05:12:58 UTC 2017

Sun Dec 3 05:13:03 UTC 2017

Sun Dec 3 05:13:08 UTC 2017

Sun Dec 3 05:13:13 UTC 2017

Sun Dec 3 05:13:18 UTC 2017

Sun Dec 3 05:13:23 UTC 2017

Sun Dec 3 05:13:28 UTC 2017

Sun Dec 3 05:13:33 UTC 2017

Sun Dec 3 05:13:38 UTC 2017

Sun Dec 3 05:13:43 UTC 2017

Sun Dec 3 05:13:48 UTC 2017

Sun Dec 3 05:13:53 UTC 2017

Sun Dec 3 05:13:58 UTC 2017

Sun Dec 3 05:14:03 UTC 2017

Sun Dec 3 05:14:08 UTC 2017

Sun Dec 3 05:14:13 UTC 2017

Sun Dec 3 05:14:18 UTC 2017

Sun Dec 3 05:14:23 UTC 2017

Sun Dec 3 05:14:28 UTC 2017

Sun Dec 3 05:14:33 UTC 2017

Sun Dec 3 05:14:38 UTC 2017

Sun Dec 3 05:14:43 UTC 2017

Sun Dec 3 05:14:48 UTC 2017

Sun Dec 3 05:14:53 UTC 2017

Sun Dec 3 05:14:58 UTC 2017

Sun Dec 3 05:15:03 UTC 2017

Sun Dec 3 05:15:08 UTC 2017

Sun Dec 3 05:15:13 UTC 2017

Sun Dec 3 05:15:18 UTC 2017

Sun Dec 3 05:15:23 UTC 2017

vskumar@ubuntu:~$

=================You can see the output for every few seconds listed =======>

It means the container is running as a daemon.

Now, let us use ps -eaf command to check the processed running in linux by using :

$ ps -eaf | grep ‘daemon’

========= See the output of daemon processes ==========>

vskumar@ubuntu:~$

vskumar@ubuntu:~$ ps -eaf | grep ‘daemon’

message+ 837 1 0 20:26 ? 00:00:05 /usr/bin/dbus-daemon –system –address=systemd: –nofork –nopidfile –systemd-activation

root 871 1 0 20:26 ? 00:00:03 /usr/sbin/NetworkManager –no-daemon

avahi 873 1 0 20:26 ? 00:00:00 avahi-daemon: running [ubuntu.local]

root 876 1 0 20:26 ? 00:00:01 /usr/lib/accountsservice/accounts-daemon

avahi 893 873 0 20:26 ? 00:00:00 avahi-daemon: chroot helper

rtkit 1370 1 0 20:28 ? 00:00:00 /usr/lib/rtkit/rtkit-daemon

vskumar 2426 1 0 20:55 ? 00:00:00 /usr/bin/gnome-keyring-daemon –daemonize –login

vskumar 2508 2428 0 20:55 ? 00:00:00 upstart-udev-bridge –daemon –user

vskumar 2515 2428 0 20:55 ? 00:00:04 dbus-daemon –fork –session –address=unix:abstract=/tmp/dbus-nPaV5rWlQc

vskumar 2570 2428 0 20:55 ? 00:00:03 /usr/lib/x86_64-linux-gnu/bamf/bamfdaemon

vskumar 2572 2428 0 20:55 ? 00:00:04 /usr/bin/ibus-daemon –daemonize –xim –address unix:tmpdir=/tmp/ibus

vskumar 2575 2428 0 20:55 ? 00:00:00 upstart-file-bridge –daemon –user

vskumar 2579 2428 0 20:55 ? 00:00:00 upstart-dbus-bridge –daemon –system –user –bus-name system

vskumar 2582 2428 0 20:55 ? 00:00:00 upstart-dbus-bridge –daemon –session –user –bus-name session

vskumar 2605 2428 0 20:55 ? 00:00:00 /usr/lib/ibus/ibus-x11 –kill-daemon

vskumar 2630 2428 0 20:56 ? 00:00:00 gpg-agent –homedir /home/vskumar/.gnupg –use-standard-socket –daemon

vskumar 2645 2428 0 20:56 ? 00:00:02 /usr/lib/unity-settings-daemon/unity-settings-daemon

vskumar 2664 2653 0 20:56 ? 00:00:00 /usr/bin/dbus-daemon –config-file=/etc/at-spi2/accessibility.conf –nofork –print-address 3

vskumar 2851 2654 0 20:56 ? 00:00:01 /usr/lib/unity-settings-daemon/unity-fallback-mount-helper

vskumar 2914 2428 0 20:57 ? 00:00:00 /bin/sh -c /usr/lib/x86_64-linux-gnu/zeitgeist/zeitgeist-maybe-vacuum; /usr/bin/zeitgeist-daemon

vskumar 2920 2914 0 20:57 ? 00:00:00 /usr/bin/zeitgeist-daemon

vskumar 3094 2428 0 21:00 ? 00:00:01 /usr/lib/x86_64-linux-gnu/unity-lens-files/unity-files-daemon

root 4148 1253 0 21:11 ? 00:00:00 docker-containerd-shim –namespace moby –workdir /var/lib/docker/containerd/daemon/io.containerd.runtime.v1.linux/moby/0fe495fc93edee3aaadc7fc0fbf21997f0ca3cde4d7e563aa8c61352a43957dd –address /var/run/docker/containerd/docker-containerd.sock –runtime-root /var/run/docker/runtime-runc

vskumar 4480 3206 0 21:19 pts/19 00:00:00 grep –color=auto daemon

vskumar@ubuntu:~$

======== You can see the list of processes running currently ========>

So we are successful! to run a container in a detached mode [not in an interactive mode!] using the command: ‘ sudo docker run -d ubuntu’

You can think in an application architecture having multiple servers or SOA running with different services.

You can simulate the same services using the docker containers, by setting up as images by configuring the required services and connect them to the architecture.

This way the advantages of containers can be utilized well. Where different companies are using and implementing their applications into containers architecture by saving lot of infrastructure cost. No hardware or physical servers are required. Lot of space also can be saved. The microservices architecture leads to the same way.

At this point, I would like to stop this session and in the next blog we will see other exercises.

Vcard-Shanthi Kumar V-v3

 

 

10. DevOps: How to Build images from Docker containers?

Docker-logo

This is in continuation of my last blog “9. DevOps: How to do Containers housekeeping ?”. In this blog I would like to demonstrate on:

How to Build images from docker containers?:

Note: If you want to recollect the docker commands to be used during your current lab practice, visit my blog link:

https://vskumarblogs.wordpress.com/2017/12/13/some-useful-docker-commands-for-handling-images-and-containers/

So far we have built the containers and operated them through the previous exercises. Now, let us see how  can we add  software to our base image on a running container and then convert that container into an image for future usage.

Let’s take ubuntu:16.04 as our base image, install the wget application, and then convert the running container to an image with the below steps:

To make ubuntu:16.04 container is our base image, we need to install the wget application, and then convert it as the running container to a docker image by using the below steps:

  1. Launch an ubuntu:16.04 container using the docker run subcommand, as shown below:
      $ sudo docker run -i -t ubuntu:16.04 /bin/bash
========================>
vskumar@ubuntu:~$ sudo docker ps -aq
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up 11 minutes                           zen_volhard
vskumar@ubuntu:~$ sudo docker run -i -t ubuntu:16.04 /bin/bash
root@3484664d454a:/# 
=========================>
2. Now, let's  verify is wget  available for this image or not.
============== the display shows there is no wget in this image =========>

root@3484664d454a:/# ls
bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var
root@3484664d454a:/# which wget
root@3484664d454a:/# 

      root@472c96295678:/# apt-get update
==================>
As we know that it is a brand new ubuntu container we built it, before installing wget we must synchronize it with the Ubuntu package repository, as shown below:
====================>
root@3484664d454a:/# apt-get update
Get:1 http://archive.ubuntu.com/ubuntu xenial InRelease [247 kB]         
Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [102 kB]                                                                      
Get:4 http://archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB]                                                                    
Get:5 http://archive.ubuntu.com/ubuntu xenial/universe Sources [9802 kB]                                                                      
Get:6 http://security.ubuntu.com/ubuntu xenial-security/universe Sources [53.1 kB]                                                            
Get:7 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages [504 kB]                                                          
Get:8 http://security.ubuntu.com/ubuntu xenial-security/restricted amd64 Packages [12.9 kB]                                                   
Get:9 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 Packages [229 kB]                                                      
Get:10 http://security.ubuntu.com/ubuntu xenial-security/multiverse amd64 Packages [3479 B]                                                   
Get:11 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages [1558 kB]                                                                  
Get:12 http://archive.ubuntu.com/ubuntu xenial/restricted amd64 Packages [14.1 kB]                                                            
Get:13 http://archive.ubuntu.com/ubuntu xenial/universe amd64 Packages [9827 kB]                                                              
Get:14 http://archive.ubuntu.com/ubuntu xenial/multiverse amd64 Packages [176 kB]                                                             
Get:15 http://archive.ubuntu.com/ubuntu xenial-updates/universe Sources [228 kB]                                                              
Get:16 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [864 kB]                                                           
Get:17 http://archive.ubuntu.com/ubuntu xenial-updates/restricted amd64 Packages [13.7 kB]                                                    
Get:18 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [711 kB]                                                       
Get:19 http://archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 Packages [18.5 kB]                                                    
Get:20 http://archive.ubuntu.com/ubuntu xenial-backports/main amd64 Packages [5174 B]                                                         
Get:21 http://archive.ubuntu.com/ubuntu xenial-backports/universe amd64 Packages [7135 B]                                                     
Fetched 24.6 MB in 59s (412 kB/s)                                                                                                             
Reading package lists... Done
root@3484664d454a:/# 
================================>
Now, we can install wget as below:
=========== Output of wget installation on container ===========>

root@3484664d454a:/# 
root@3484664d454a:/# apt-get install -y wget
Reading package lists... Done
Building dependency tree        
Reading state information... Done
The following additional packages will be installed:
  ca-certificates libidn11 libssl1.0.0 openssl
The following NEW packages will be installed:
  ca-certificates libidn11 libssl1.0.0 openssl wget
0 upgraded, 5 newly installed, 0 to remove and 1 not upgraded.
Need to get 2089 kB of archives.
After this operation, 6027 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libidn11 amd64 1.32-3ubuntu1.2 [46.5 kB]
Get:2 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 libssl1.0.0 amd64 1.0.2g-1ubuntu4.9 [1085 kB]
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 openssl amd64 1.0.2g-1ubuntu4.9 [492 kB]
Get:4 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 ca-certificates all 20170717~16.04.1 [168 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 wget amd64 1.17.1-1ubuntu1.3 [299 kB]
Fetched 2089 kB in 4s (421 kB/s)
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package libidn11:amd64.
(Reading database ... 4768 files and directories currently installed.)
Preparing to unpack .../libidn11_1.32-3ubuntu1.2_amd64.deb ...
Unpacking libidn11:amd64 (1.32-3ubuntu1.2) ...
Selecting previously unselected package libssl1.0.0:amd64.
Preparing to unpack .../libssl1.0.0_1.0.2g-1ubuntu4.9_amd64.deb ...
Unpacking libssl1.0.0:amd64 (1.0.2g-1ubuntu4.9) ...
Selecting previously unselected package openssl.
Preparing to unpack .../openssl_1.0.2g-1ubuntu4.9_amd64.deb ...
Unpacking openssl (1.0.2g-1ubuntu4.9) ...
Selecting previously unselected package ca-certificates.
Preparing to unpack .../ca-certificates_20170717~16.04.1_all.deb ...
Unpacking ca-certificates (20170717~16.04.1) ...
Selecting previously unselected package wget.
Preparing to unpack .../wget_1.17.1-1ubuntu1.3_amd64.deb ...
Unpacking wget (1.17.1-1ubuntu1.3) ...
Processing triggers for libc-bin (2.23-0ubuntu9) ...
Setting up libidn11:amd64 (1.32-3ubuntu1.2) ...
Setting up libssl1.0.0:amd64 (1.0.2g-1ubuntu4.9) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.22.1 /usr/local/share/perl/5.22.1 /usr/lib/x86_64-linux-gnu/perl5/5.22 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.22 /usr/share/perl/5.22 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base .) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Setting up openssl (1.0.2g-1ubuntu4.9) ...
Setting up ca-certificates (20170717~16.04.1) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.22.1 /usr/local/share/perl/5.22.1 /usr/lib/x86_64-linux-gnu/perl5/5.22 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.22 /usr/share/perl/5.22 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base .) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Setting up wget (1.17.1-1ubuntu1.3) ...
Processing triggers for libc-bin (2.23-0ubuntu9) ...
Processing triggers for ca-certificates (20170717~16.04.1) ...
Updating certificates in /etc/ssl/certs...
148 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d...
done.
root@3484664d454a:/# 
=========================== End of installation ===========>
Now, we can verify with  'which wget ' command
============>
root@3484664d454a:/# which wget
/usr/bin/wget
root@3484664d454a:/# 
============>
Please let us recollect; installation of any software would alter the Dockwer base image composition. In which, we can also trace using the docker diff subcommand as we did in the previous exercises. 
I will open a second Terminal/screen, the docker diff subcommand can be issued from it, as below:
      $ sudo docker diff 472c96295678
===============>
vskumar@ubuntu:~$  
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
3484664d454a        ubuntu:16.04        "/bin/bash"         15 minutes ago      Up 15 minutes                           jolly_cray
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up 40 minutes                           zen_volhard
vskumar@ubuntu:~$ sudo docker diff 155f4b0764b1
C /root
A /root/.bash_history
vskumar@ubuntu:~$ 
============>

How to save this container ?:
The docker commit subcommand can be performed on a running or a stopped container. When a commit is performed on a running container, the Docker Engine pauses the container during the commit operation in order to avoid any data inconsistency. 
Now we can stop our running container.
We can commit a container to an image with the docker commit subcommand, as shown here:
      $ sudo docker commit 

================== Using commit for container ============>

root@3484664d454a:/# 
root@3484664d454a:/# exit
exit
vskumar@ubuntu:~$ sudo docker commit 3484664d454a
[sudo] password for vskumar: 
Sorry, try again.
[sudo] password for vskumar: 
sha256:fc7e4564eb928ccfe068c789f0d650967e8d5dc42d4e8d92409aab6614364075
vskumar@ubuntu:~$ 
=======================>
You can see the container id from the above output.

=========== We can also give a message to the commit command as below ===>
vskumar@ubuntu:~$ sudo docker commit 3484664d454a  Docker-exercise/ubuntu-wgetinstall
invalid reference format: repository name must be lowercase
vskumar@ubuntu:~$ sudo docker commit 3484664d454a  docker-exercise/ubuntu-wgetinstall
sha256:e34304119838d79da60e12776529106c350b1972cd517648e8ab90311fad7b1a
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                       PORTS               NAMES
3484664d454a        ubuntu:16.04        "/bin/bash"         24 minutes ago      Exited (130) 6 minutes ago                       jolly_cray
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up About an hour                                 zen_volhard
vskumar@ubuntu:~$ 
===================== Note there are two containers created  ====>
Now, I want to remove one container :
==========>

vskumar@ubuntu:~$ sudo docker rm 3484664d454a
3484664d454a
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         3 hours ago         Up About an hour                        zen_volhard
vskumar@ubuntu:~$ 
========================>

Now let us check the docker images how many we have in our store :
=========== List of images ==========>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker images
REPOSITORY                           TAG                 IMAGE ID            CREATED             SIZE
docker-exercise/ubuntu-wgetinstall   latest              e34304119838        5 minutes ago       169MB
<none>                               <none>              fc7e4564eb92        7 minutes ago       169MB
hello-world                          latest              f2a91732366c        5 days ago          1.85kB
ubuntu                               16.04               20c44cd7596f        8 days ago          123MB
ubuntu                               latest              20c44cd7596f        8 days ago          123MB
busybox                              latest              6ad733544a63        3 weeks ago         1.13MB
busybox                              1.24                47bcc53f74dc        20 months ago       1.11MB
vskumar@ubuntu:~$ 

==============================>
How to remove images:

by using :

sudo docker rmi image [image id], we can remove the image. For example; if you want to remove the image id:
47bcc53f74dc
you can use: $ sudo docker rmi image 47bcc53f74dc
=================>
vskumar@ubuntu:~$ sudo docker rmi image 47bcc53f74dc
Untagged: busybox:1.24
Untagged: busybox@sha256:8ea3273d79b47a8b6d018be398c17590a4b5ec604515f416c5b797db9dde3ad8
Deleted: sha256:47bcc53f74dc94b1920f0b34f6036096526296767650f223433fe65c35f149eb
Deleted: sha256:f6075681a244e9df4ab126bce921292673c9f37f71b20f6be1dd3bb99b4fdd72
Deleted: sha256:1834950e52ce4d5a88a1bbd131c537f4d0e56d10ff0dd69e66be3b7dfa9df7e6
Error: No such image: image
vskumar@ubuntu:~$ 
=================>
 

So by using :

sudo docker rmi image [image id], we can remove the image.  Just recollect the difference between the image removal and container removal. For containers removal refer to my blog on "Housekeeping containers". Now we have learned how to create an image from containers using a few easy steps by installing the wget application. You can also add some other software applications to the same or different container(s) in the similar way.

You can use this method for testing also.  Let us say, you want to test a set of java programs. Then you need to install jdk and copy your programs. Write a shell script to compile and execute the programs by piping their output into a text file in a Linux background. So this way, you will be using the container as a test environment also.

The most easy and recommended way of creating an image is to use the Dockerfile method.

Within dockerfile we can mention the setup required to build a container through different steps. Then dockerfile creates the required setup for a container, under docker’s building activity.

We will see it in future exercises.

Please leave your feedback!

Vcard-Shanthi Kumar V-v39. DevOps: How to do Containers housekeeping ?

7. DevOps: How to track changes in a container

Docker-logo

In  continuation of my previous blog on “6. DevOps: How to work with interactive docker containers”, in this blog I would like to show some lab practice “How to track changes in a container”.

Tracking changes inside containers:

Now, let us see the container operations and tracking them.

Let’s launch a container in interactive mode, as we have done in previous session, we can use the below command.

$ sudo docker run -i -t ubuntu:16.04 /bin/bash 
=================>
vskumar@ubuntu:/var/log$ sudo docker run -i -t ubuntu:16.04 /bin/bash  
root@718636415a7f:/# ps
   PID TTY          TIME CMD
     1 pts/0    00:00:00 bash
     9 pts/0    00:00:00 ps
root@718636415a7f:/# ps -ef
UID         PID   PPID  C STIME TTY          TIME CMD
root          1      0  0 12:39 pts/0    00:00:00 /bin/bash
root         10      1  0 12:53 pts/0    00:00:00 ps -ef
root@718636415a7f:/# ls
bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var
root@718636415a7f:/# 
======================>
Now, let us go to home directory:
========>
root@718636415a7f:/# pwd
/
root@718636415a7f:/# cd home
root@718636415a7f:/home# pwd
/home
root@718636415a7f:/home# ls
root@718636415a7f:/home# 
==============>
Now, as a standalone machine of this docker container, 
I want to create 4 text files using touch command as below:
==============>
root@718636415a7f:/home# ls
root@718636415a7f:/home# ls -l
total 0
root@718636415a7f:/home# touch {vsk1,vsk2,vsk3,vsk4}
root@718636415a7f:/home# ls -l
total 0
-rw-r--r-- 1 root root 0 Nov 25 12:57 vsk1
-rw-r--r-- 1 root root 0 Nov 25 12:57 vsk2
-rw-r--r-- 1 root root 0 Nov 25 12:57 vsk3
-rw-r--r-- 1 root root 0 Nov 25 12:57 vsk4
root@718636415a7f:/home# 
======================>

I am adding some text to each of them as below:

====================>

root@718636415a7f:/home# pwd

/home

root@718636415a7f:/home# echo ‘Testing vsk1’ > vsk1

root@718636415a7f:/home# ls -l

total 4

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk1

-rw-r–r– 1 root root 0 Nov 25 12:57 vsk2

-rw-r–r– 1 root root 0 Nov 25 12:57 vsk3

-rw-r–r– 1 root root 0 Nov 25 12:57 vsk4

root@718636415a7f:/home# echo ‘Testing vsk2’ > vsk2

root@718636415a7f:/home# echo ‘Testing vsk3’ > vsk3

root@718636415a7f:/home# echo ‘NOT Testing vsk4’ > vsk4

root@718636415a7f:/home# ls -l

total 16

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk1

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk2

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk3

-rw-r–r– 1 root root 17 Nov 25 13:02 vsk4

root@718636415a7f:/home#

=====================>

I have created 4 files and added some text into them.

Now, I want to execute a diff command on them:

==========================>

root@718636415a7f:/home# diff vsk1 vsk2

1c1

< Testing vsk1

> Testing vsk2

root@718636415a7f:/home# diff vsk2 vsk3

1c1

< Testing vsk2

> Testing vsk3

root@718636415a7f:/home# echo ‘NOT Testing vsk4’ > vsk1

root@718636415a7f:/home# diff vsk1 vsk4

root@718636415a7f:/home# diff vsk2 vsk4

1c1

< Testing vsk2

> NOT Testing vsk4

root@718636415a7f:/home#

===========================>

Now, I want to exit this container and go back to docker host.

I have detached it using exit.

And back to docker host.

Now, I want to use the diff command as below from host machine to the container:

===========================>

root@718636415a7f:/home# ls -l

total 16

-rw-r–r– 1 root root 17 Nov 25 13:05 vsk1

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk2

-rw-r–r– 1 root root 13 Nov 25 13:02 vsk3

-rw-r–r– 1 root root 17 Nov 25 13:02 vsk4

root@718636415a7f:/home# exit

exit

vskumar@ubuntu:/var/log$ sudo docker diff 718636415a7f

[sudo] password for vskumar:

C /home

A /home/vsk1

A /home/vsk2

A /home/vsk3

A /home/vsk4

C /root

A /root/.bash_history

vskumar@ubuntu:/var/log$

=====================>

The 1st line ‘C /home’ shows; the home directory is modified by showing ‘C’ as changed.

The ‘A’ shows;  before each line denotes the file is added.

If you have a deleted file, it can show as ‘D’ before the file.

Also please let us note here on how docker engine picks up the image with the below priority;

When we work with an image and if we don’t specify that image name, then the latest image (recently generated) will be identified and used by the Docker Engine.

We can check the status of the containers as below using ps -a:

You can see a detailed output from this command from the below display:

==================================>

vskumar@ubuntu:/var/log$ ls

alternatives.log bootstrap.log dmesg fsck kern.log speech-dispatcher unattended-upgrades wtmp

apport.log btmp dpkg.log gpu-manager.log lastlog syslog upstart Xorg.0.log

apt cups faillog hp lightdm syslog.1 vmware Xorg.0.log.old

auth.log dist-upgrade fontconfig.log installer samba syslog.2.gz vmware-vmsvc.log

vskumar@ubuntu:/var/log$ sudo docker ps -a

CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES

cb1ff260d48e ubuntu “ls /usr/src” 3 minutes ago Exited (0) 3 minutes ago wonderful_hawking

b20691fd8fb5 ubuntu “ls /usr” 3 minutes ago Exited (0) 3 minutes ago friendly_mirzakhani

431ba4c53028 ubuntu “ls” 3 minutes ago Exited (0) 3 minutes ago affectionate_nobel

2c31684bb1f4 ubuntu “ls -la” 3 minutes ago Exited (0) 3 minutes ago zealous_meitner

fe2e3b449daf ubuntu “ls -la /home/.” 4 minutes ago Exited (0) 4 minutes ago dreamy_shirley

c44bdd05b94d ubuntu “ls -la home.” 4 minutes ago Exited (2) 4 minutes ago elastic_pasteur

8b8afa82859a ubuntu “ls -la” 4 minutes ago Exited (0) 4 minutes ago festive_panini

2811eb37af61 ubuntu “ls -la 604831dbce2a” 4 minutes ago Exited (2) 4 minutes ago jolly_swartz

604831dbce2a ubuntu:16.04 “/bin/bash” 8 minutes ago Exited (0) 6 minutes ago vibrant_ride

718636415a7f ubuntu:16.04 “/bin/bash” 45 minutes ago Exited (0) 18 minutes ago reverent_noyce

53a7751d4673 ubuntu:16.04 “/bin/bash” 2 hours ago Exited (0) 2 hours ago musing_chandrasekhar

32bc16b508d4 ubuntu “bash” 3 hours ago Exited (0) 3 hours ago eager_goldberg

1dd55efde43f hello-world “/hello” 3 hours ago Exited (0) 3 hours ago peaceful_pasteur

a744246ffb8e hello-world “/hello” 5 hours ago Exited (0) 5 hours ago naughty_wing

1ba71598b7b8 hello-world “/hello” 5 hours ago Exited (0) 5 hours ago musing_kare

vskumar@ubuntu:/var/log$

============================>

I would like to terminate the session at this point. In the next blog I would like to present “How to control and operate docker containers”.

Vcard-Shanthi Kumar V-v3

6. DevOps: How to work with interactive Docker containers

Docker-logo

In  continuation of my previous blog on “5. DevOps: How to work with Docker Images”, in this blog I would like to show some lab practice on Interactive Docker containers.

Working with an interactive Docker container:

In the previous lab session, we worked with first Hello World container. And we came to know how the containerization works. Now, we are going to run a container in interactive mode.

What is docker run command ?:

The docker run subcommand takes an image as an input and launches it as a container.

What flags we need to use ?:

We have to pass the -t and -i flags to the docker run subcommand in order to make the container interactive.

The -i flag is the key driver, it makes the container interactive by grabbing the standard input (STDIN) of the container into the terminal.

The -t flag allocates a pseudo-TTY or a pseudo Terminal (Terminal emulator) and then assigns that to the container.

Note: Please note in the earlier session we have executed a container on unbuntu name.

But now, we will explore completely the interactive container operations.

In the below example, we are going to launch an interactive container using the ubuntu:16.04 image and /bin/bash as the command:

$ sudo docker run -i -t ubuntu:16.04 /bin/bash 

=========== Output ============>

vskumar@ubuntu:/var/log$ sudo docker run -i -t ubuntu:16.04 /bin/bash

Unable to find image ‘ubuntu:16.04’ locally

16.04: Pulling from library/ubuntu

Digest: sha256:7c67a2206d3c04703e5c23518707bdd4916c057562dd51c74b99b2ba26af0f79

Status: Downloaded newer image for ubuntu:16.04

root@53a7751d4673:/#

===================>

Why the error messages [Unable to find image] appear ?:

As the ubuntu 16.04 image is not downloaded yet, we get the above message and with the docker run command it will start pulling the ubuntu 16.04 image automatically with following message:

Unable to find image 'ubuntu:16.04' locally
16.04: Pulling from library/ubuntu

When the download is completed, the container will get launched along with the ubuntu:16.04 image.

It will also launch a Bash shell within the container, because we have specified /bin/bash as the command to be executed. This landed us in a Bash prompt, as shown below:

root@53a7751d4673:/#

What is ’53a7751d4673′?:

It is the hostname of the container. In Docker, the hostname is the same as the container ID.

Now, let us run a few commands interactively and confirm what we mentioned about the prompt is correct, as shown below:

To check the hostname below commands need to be executed:

root@53a7751d4673:/# hostname

root@53a7751d4673:/# id

root@53a7751d4673:/# echo $PS1

When we execute them, can see the below output:

==============>

root@53a7751d4673:/#

root@53a7751d4673:/# hostname

53a7751d4673

root@53a7751d4673:/# id

uid=0(root) gid=0(root) groups=0(root)

root@53a7751d4673:/# echo $PS1

\[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\u@\h:\w\$

root@53a7751d4673:/#

=====================>

So, we have seen the Host name as ’53a7751d4673′.

Id as ‘root ‘

Using ‘PS1’, —>Displays username, hostname and current working directory in the prompt.

PS1 in this example displays the following three information in the prompt:

\[\e]0;\u@\h: \w\a\]${debian_chroot:+($debian_chroot)}\u@\h:\w\$

  • \u – Username
  • \h – Hostname
  • \w – Full path of the current working directory

==============>

root@53a7751d4673:/# pwd

/

root@53a7751d4673:/#

==========>

Note, we are within the ubuntu 16.04 container and it works as Linux machine. So we can try some Linux commands also:

===============>

root@53a7751d4673:/# ps

PID TTY TIME CMD

1 pts/0 00:00:00 bash

26 pts/0 00:00:00 ps

root@53a7751d4673:/# ps -ef

UID PID PPID C STIME TTY TIME CMD

root 1 0 0 11:28 pts/0 00:00:00 /bin/bash

root 27 1 0 11:48 pts/0 00:00:00 ps -ef

root@53a7751d4673:/#

root@53a7751d4673:/# ls

bin boot dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var

root@53a7751d4673:/# ls -l

total 64

drwxr-xr-x 2 root root 4096 Nov 14 13:49 bin

drwxr-xr-x 2 root root 4096 Apr 12 2016 boot

drwxr-xr-x 5 root root 360 Nov 25 11:28 dev

drwxr-xr-x 45 root root 4096 Nov 25 11:28 etc

drwxr-xr-x 2 root root 4096 Apr 12 2016 home

drwxr-xr-x 8 root root 4096 Sep 13 2015 lib

drwxr-xr-x 2 root root 4096 Nov 14 13:49 lib64

drwxr-xr-x 2 root root 4096 Nov 14 13:48 media

drwxr-xr-x 2 root root 4096 Nov 14 13:48 mnt

drwxr-xr-x 2 root root 4096 Nov 14 13:48 opt

dr-xr-xr-x 250 root root 0 Nov 25 11:28 proc

drwx—— 2 root root 4096 Nov 14 13:49 root

drwxr-xr-x 6 root root 4096 Nov 14 13:49 run

drwxr-xr-x 2 root root 4096 Nov 17 21:59 sbin

drwxr-xr-x 2 root root 4096 Nov 14 13:48 srv

dr-xr-xr-x 13 root root 0 Nov 25 11:28 sys

drwxrwxrwt 2 root root 4096 Nov 14 13:49 tmp

drwxr-xr-x 11 root root 4096 Nov 14 13:48 usr

drwxr-xr-x 13 root root 4096 Nov 14 13:49 var

root@53a7751d4673:/#

================>

So, ubuntu 16.04 container is nothing but a linux machine and we executed the above commands.

Now, I want to change the root permissions as below:

==============>

root@53a7751d4673:/# chmod +777 root

root@53a7751d4673:/# ls -l

total 64

drwxr-xr-x 2 root root 4096 Nov 14 13:49 bin

drwxr-xr-x 2 root root 4096 Apr 12 2016 boot

drwxr-xr-x 5 root root 360 Nov 25 11:28 dev

drwxr-xr-x 45 root root 4096 Nov 25 11:28 etc

drwxr-xr-x 2 root root 4096 Apr 12 2016 home

drwxr-xr-x 8 root root 4096 Sep 13 2015 lib

drwxr-xr-x 2 root root 4096 Nov 14 13:49 lib64

drwxr-xr-x 2 root root 4096 Nov 14 13:48 media

drwxr-xr-x 2 root root 4096 Nov 14 13:48 mnt

drwxr-xr-x 2 root root 4096 Nov 14 13:48 opt

dr-xr-xr-x 255 root root 0 Nov 25 11:28 proc

drwxrwxrwx 2 root root 4096 Nov 14 13:49 root

drwxr-xr-x 6 root root 4096 Nov 14 13:49 run

drwxr-xr-x 2 root root 4096 Nov 17 21:59 sbin

drwxr-xr-x 2 root root 4096 Nov 14 13:48 srv

dr-xr-xr-x 13 root root 0 Nov 25 11:48 sys

drwxrwxrwt 2 root root 4096 Nov 14 13:49 tmp

drwxr-xr-x 11 root root 4096 Nov 14 13:48 usr

drwxr-xr-x 13 root root 4096 Nov 14 13:49 var

root@53a7751d4673:/#

================>

Now, I want to exit from container and come back to host machine.

==================>

root@53a7751d4673:/#

root@53a7751d4673:/# exit

exit

vskumar@ubuntu:/var/log$

===============>

Whenever the Bash exit command is used in the interactive container, it will terminate the Bash shell process.

In turn it will stop the container and returns to the docker host machine.

As a result, we can see the Docker host’s prompt $


You can see the status of docker images as below when I used ‘sudo docker images’ :

==================>

vskumar@ubuntu:/var/log$

vskumar@ubuntu:/var/log$ sudo docker images

REPOSITORY TAG IMAGE ID CREATED SIZE

hello-world latest f2a91732366c 4 days ago 1.85kB

ubuntu 16.04 20c44cd7596f 7 days ago 123MB

ubuntu latest 20c44cd7596f 7 days ago 123MB

busybox latest 6ad733544a63 3 weeks ago 1.13MB

busybox 1.24 47bcc53f74dc 20 months ago 1.11MB

vskumar@ubuntu:/var/log$

=====================>

You can see whatever containers; we have have used in the past exercises.

At this point, I would like to stop this lab session. And in the next blog we can see on “How to track changes in a container?”.

 

Vcard-Shanthi Kumar V

 

 

5. DevOps: How to work with Docker Images

Docker-logo

In  continuation of my previous blog on “4. DevOps: How to work with Docker Containers”, in this blog I would like to give some lab practice on Docker Images.

How to pull the docker public images ?:
Docker portal will have numerous images available  under public.
Now, there is a need for us to know the usage of docker pull command, which is the defacto command to download Docker images.

Now, in this section, we will use the busybox image, one of the smallest but a very handy Docker image, to dive deep into Docker image handling:
$sudo docker pull busybox
============= Output ============>
vskumar@ubuntu:/var/tmp$ sudo docker pull busybox
Using default tag: latest
latest: Pulling from library/busybox
0ffadd58f2a6: Pull complete
Digest: sha256:bbc3a03235220b170ba48a157dd097dd1379299370e1ed99ce976df0355d24f0
Status: Downloaded newer image for busybox:latest
vskumar@ubuntu:/var/tmp$
=================>
Sometimes it might reject this request. We need to keep on trying to get it. I tried 4 times at different timings to connect to it.
Please note now, we have three images as below through all of our so far exercises:
===================>
vskumar@ubuntu:/var/log$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
hello-world latest f2a91732366c 4 days ago 1.85kB
ubuntu latest 20c44cd7596f 7 days ago 123MB
busybox latest 6ad733544a63 3 weeks ago 1.13MB
vskumar@ubuntu:/var/log$
===============>
Now, let us stop the docker services and check the status as below:
=================>
vskumar@ubuntu:/var/log$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
hello-world latest f2a91732366c 4 days ago 1.85kB
ubuntu latest 20c44cd7596f 7 days ago 123MB
busybox latest 6ad733544a63 3 weeks ago 1.13MB
vskumar@ubuntu:/var/log$ sudo service docker stop
vskumar@ubuntu:/var/log$ sudo service docker status
● docker.service – Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: e
Active: inactive (dead) since Sat 2017-11-25 02:52:25 PST; 8s ago
Docs: https://docs.docker.com
Process: 1224 ExecStart=/usr/bin/dockerd -H fd:// (code=exited, status=0/SUCCE
Main PID: 1224 (code=exited, status=0/SUCCESS)
Nov 25 02:21:42 ubuntu dockerd[1224]: time=”2017-11-25T02:21:42.863518710-08:00″
Nov 25 02:21:43 ubuntu dockerd[1224]: time=”2017-11-25T02:21:43-08:00″ level=inf
Nov 25 02:27:08 ubuntu dockerd[1224]: time=”2017-11-25T02:27:08.010096274-08:00″
Nov 25 02:27:08 ubuntu dockerd[1224]: time=”2017-11-25T02:27:08-08:00″ level=inf
Nov 25 02:27:08 ubuntu dockerd[1224]: time=”2017-11-25T02:27:08.199685599-08:00″
Nov 25 02:52:25 ubuntu dockerd[1224]: time=”2017-11-25T02:52:25.010875880-08:00″
Nov 25 02:52:25 ubuntu systemd[1]: Stopping Docker Application Container Engine.
Nov 25 02:52:25 ubuntu dockerd[1224]: time=”2017-11-25T02:52:25.081714537-08:00″
Nov 25 02:52:25 ubuntu systemd[1]: Stopped Docker Application Container Engine.
Nov 25 02:52:25 ubuntu systemd[1]: Stopped Docker Application Container Engine.
vskumar@ubuntu:/var/log$
====================>
You can see the inactive status of docker.
In such cases, restart the Docker service, as shown here:

$ sudo service docker restart
You can see the output as below:
==================>
vskumar@ubuntu:/var/log$ sudo service docker restart
vskumar@ubuntu:/var/log$ sudo service docker status 
docker.service - Docker Application Container Engine
   Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: e
   Active: active (running) since Sat 2017-11-25 02:54:42 PST; 6s ago
     Docs: https://docs.docker.com
 Main PID: 3769 (dockerd)
    Tasks: 18
   Memory: 24.6M
      CPU: 989ms
   CGroup: /system.slice/docker.service
           ├─3769 /usr/bin/dockerd -H fd://
           └─3778 docker-containerd --config /var/run/docker/containerd/containe

Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.159062708-08:00"
Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.159806997-08:00"
Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.163503112-08:00"
Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.743276580-08:00"
Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.955217284-08:00"
Nov 25 02:54:41 ubuntu dockerd[3769]: time="2017-11-25T02:54:41.975961283-08:00"
Nov 25 02:54:42 ubuntu dockerd[3769]: time="2017-11-25T02:54:42.092220161-08:00"
Nov 25 02:54:42 ubuntu dockerd[3769]: time="2017-11-25T02:54:42.094334663-08:00"
Nov 25 02:54:42 ubuntu systemd[1]: Started Docker Application Container Engine.
Nov 25 02:54:42 ubuntu dockerd[3769]: time="2017-11-25T02:54:42.190194886-08:00"

vskumar@ubuntu:/var/log$ 

========================>

Now, let us reconfirm the existing docker images as below:
================>

vskumar@ubuntu:/var/log$ ^C
vskumar@ubuntu:/var/log$ sudo docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
hello-world         latest              f2a91732366c        4 days ago          1.85kB
ubuntu              latest              20c44cd7596f        7 days ago          123MB
busybox             latest              6ad733544a63        3 weeks ago         1.13MB
vskumar@ubuntu:/var/log$ 
=======================>

By default, Docker always uses the image that is tagged as latest.

Each image variant can be directly identified by qualifying it with an appropriate tag.

An image can be tag-qualified by adding a colon (:) between the tag and the repository name (<repository>:<tag>). For demonstration, we will pull the 1.24 tagged version of busybox as shown here:

Now, For lab demonstration, we will pull the 1.24 tagged version of busybox as shown here:

$ sudo docker pull busybox:1.24

Now. You can see the total output before and after executing the above command:

==============================>

vskumar@ubuntu:/var/log$ ^C

vskumar@ubuntu:/var/log$ sudo docker images

REPOSITORY TAG IMAGE ID CREATED SIZE

hello-world latest f2a91732366c 4 days ago 1.85kB

ubuntu latest 20c44cd7596f 7 days ago 123MB

busybox latest 6ad733544a63 3 weeks ago 1.13MB

vskumar@ubuntu:/var/log$ ^C

vskumar@ubuntu:/var/log$

vskumar@ubuntu:/var/log$

vskumar@ubuntu:/var/log$ sudo docker pull busybox:1.24

1.24: Pulling from library/busybox

385e281300cc: Pull complete

a3ed95caeb02: Pull complete

Digest: sha256:8ea3273d79b47a8b6d018be398c17590a4b5ec604515f416c5b797db9dde3ad8

Status: Downloaded newer image for busybox:1.24

vskumar@ubuntu:/var/log$ sudo docker images

REPOSITORY TAG IMAGE ID CREATED SIZE

hello-world latest f2a91732366c 4 days ago 1.85kB

ubuntu latest 20c44cd7596f 7 days ago 123MB

busybox latest 6ad733544a63 3 weeks ago 1.13MB

busybox 1.24 47bcc53f74dc 20 months ago 1.11MB

vskumar@ubuntu:/var/log$

==============================>

There are two busybox containers with different versions.

So, on the basis of TAG values the containers are being pulled.

How to Search Docker images:

So far we have pulled the known images from the docker-hub.

Let us identify some docker images by using a search option as below. We can search for Docker images in the Docker Hub Registry using the docker search subcommand, as shown in this example:

$ sudo docker search mysql

You can see the displayed output of mysql images from the Docker Hub Registry:

=============>

vskumar@ubuntu:/var/log$ sudo docker search mysql

NAME DESCRIPTION STARS OFFICIAL AUTOMATED

mysql MySQL is a widely used, open-source relation… 5278 [OK]

mariadb MariaDB is a community-developed fork of MyS… 1634 [OK]

mysql/mysql-server Optimized MySQL Server Docker images. Create… 368 [OK]

percona Percona Server is a fork of the MySQL relati… 303 [OK]

hypriot/rpi-mysql RPi-compatible Docker Image with Mysql 74

zabbix/zabbix-server-mysql Zabbix Server with MySQL database support 64 [OK]

centurylink/mysql Image containing mysql. Optimized to be link… 53 [OK]

sameersbn/mysql 48 [OK]

zabbix/zabbix-web-nginx-mysql Zabbix frontend based on Nginx web-server wi… 38 [OK]

tutum/mysql Base docker image to run a MySQL database se… 29

1and1internet/ubuntu-16-nginx-php-phpmyadmin-mysql-5 ubuntu-16-nginx-php-phpmyadmin-mysql-5 17 [OK]

schickling/mysql-backup-s3 Backup MySQL to S3 (supports periodic backup… 16 [OK]

centos/mysql-57-centos7 MySQL 5.7 SQL database server 15

linuxserver/mysql A Mysql container, brought to you by LinuxSe… 12

centos/mysql-56-centos7 MySQL 5.6 SQL database server 6

openshift/mysql-55-centos7 DEPRECATED: A Centos7 based MySQL v5.5 image… 6

frodenas/mysql A Docker Image for MySQL 3 [OK]

dsteinkopf/backup-all-mysql backup all DBs in a mysql server 3 [OK]

circleci/mysql MySQL is a widely used, open-source relation… 2

cloudfoundry/cf-mysql-ci Image used in CI of cf-mysql-release 0

cloudposse/mysql Improved `mysql` service with support for `m… 0 [OK]

ansibleplaybookbundle/rhscl-mysql-apb An APB which deploys RHSCL MySQL 0 [OK]

astronomerio/mysql-sink MySQL sink 0 [OK]

inferlink/landmark-mysql landmark-mysql 0 [OK]

astronomerio/mysql-source MySQL source 0 [OK]

vskumar@ubuntu:/var/log$ ^C

vskumar@ubuntu:/var/log$

====================>

You can get the top 5 images by suing head -5 linux command.

$sudo docker search mysql | head -5

=============>

vskumar@ubuntu:/var/log$ sudo docker search mysql | head -5

NAME DESCRIPTION STARS OFFICIAL AUTOMATED

mysql MySQL is a widely used, open-source relation… 5278 [OK]

mariadb MariaDB is a community-developed fork of MyS… 1634 [OK]

mysql/mysql-server Optimized MySQL Server Docker images. Create… 368 [OK]

percona Percona Server is a fork of the MySQL relati… 303 [OK]

vskumar@ubuntu:/var/log$

===============>

If you see the above list, The mysql image curated and hosted by Docker Inc has a 5278 star rating, which is indicated as this is the most popular mysql image and aslo as Official image to use it. For security reasons we should use the official and highly rated images only.

As we planned, in this blog we have worked with the Docker images.

At this point we can stop this session and in the next blog we can see on “How to work with interactive containers”.

Vcard-Shanthi Kumar V-v3

Feel free to Contact me :

 

3. DevOps – Jenkins[2.9]: How to create and build the job ?

jenkins

In continuation of my previous blog on Jenkins 2.9 installation [https://vskumar.blog/2017/11/25/1-devops-jenkins2-9-installation-with-java-9-on-windows-10], We have installed and retested it. In this blog we can see a simple job creation and running it in a build.

Now, Let us do some exercise:

Let us create a new job using Jenkins.

As you are aware of; with Jenkins any kind of manual tasks can be done.

For example:

  1. I want to compile a java program and run it.
  2. To do this 1st let us identify the manual steps.
  3. I need to go to the below directory: D:\JavaSamples\Javatest , where my java programs are available.
  4. I need to use the below command:

CD [to know the current directory.]

Assume, I am in the below dir:

D:\Jenkins\jenkins-2.90>cd

D:\Jenkins\jenkins-2.90

Then , I need to use cd \JavaSamples\Javatest

Now I need to check my current path using cd

Then see the hello*.java using

dir command.

Then I need to compile it using ‘javac HellowWorld.java’ command.

Then I need to check the files on hello*.* name

There should be one file as ‘HellowWorld.class’

It means my program has been compiled correctly without errors.

Now, I need to run the program using java command.

Now, I need to run this file as java HellowWorld

It should display the output.

I have executed all the steps in a command window to compile and test the program.

You can see the executed commands and the  output also from the below screen:

HelloWorld-compile&amp;execute-CMD

As we know these are the manual tasks we need to do repetetively to select a program, compile it and run it. Why don’t we use Jenkins to create a job which has these set of tasks.

Now, let us learn how to create a job in Jenkins?:

Now assuming you are on the below screen:

Jenkins-New Job Creation

Click on “create new jobs”

You will get the below screen:

Jenkins job creation-enter an item name scrn.png

I want to create a job with the name of “vskumar2017test1”.

Jenkins-Freestyle project-creation

I want to create a Freestyle project, as I do not work with any of the plugins for now.
Hence I need to select on the 1st option “ Freestyle project”. When I click on “OK” button, we can see the below screen:

Jenkins-Freestyle project-creation2

I have entered the project description as below, as per our activity plan:

Jenkins-Freestyle project-description

As you are aware we are using Jenkins for simple task in this exercise,

Now click on build options. You will get the below screen:

Jenkins-Freestyle project-Build.png

In this screen we need to use build option. So click on add build steps. Using this option, we will get the below features to use the command window and the commands:

Jenkins-Freestyle project-Build-Add build step

There are two different options we can see to use the commands execution. 1. Execute Windows batch command , 2. Execute shell. Currently e are working with windows only. Hence 1st option need to be selected.

You can see the below screen:

Jenkins-New Job-Build-window commands1

Now, whatever commands we tried using command prompt we need to enter those.

For example I used as below:

cd

cd \JavaSamples\Javatest

dir hellow*.java

javac HellowWorld.java

dir HellowWorld.*

java HellowWorld

Now, I am copying these commands into the window. You can see the partially displayed commands in the window. In reality it has all the commands.

Jenkins-Build-Windows-batch commands-entry1

Now, let us save this job.
We will get the below screen on the created job name:

Jenkins-Project-vskumar2017test1.png

How to run the created project ?:

We need to run the created project using the option “Build now”.

You can see the build history as the job running, Under build#1.

Now, How to see the executed job output ?:
To see the output we need to click on the down arrow mark ate the job#.
It displays the below:

We need to select the console output, It displays the output as below:

Jenkins-Project-vskumar2017test1-running-build1-consoleOuputIf we scroll down we can see the job status message:

Jenkins-Project-vskumar2017test1-running-build1-consoleOuput

It shows all the output for our commands along with the job status.

Now let us review and analyze the display messages and commands as below.

Started by user Vskumar2017
Building in workspace D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1
[vskumar2017test1] $ cmd /c call C:\WINDOWS\TEMP\jenkins5234154176626743505.bat

The above commands shows, Jenkins started the job with user id vskumar2017.N

And it displays the current path of the job where it is created.

And it invokes a .bat file to execute the command prompt commands what we entered. It means it stored the batch commands into a file and it is opened by a cmd command from a shell prompt.

Now, let us see the below commands:

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd
D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1

It denotes its current job/project directory. And executed the cd to show the path.

Through the below:

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd  \JavaSamples\Javatest 

D:\JavaSamples\Javatest>dir hellow*.java 
 Volume in drive D is New Volume
 Volume Serial Number is 5C67-6F04

 Directory of D:\JavaSamples\Javatest

04/16/2017  03:52 PM               234 HellowWorld.java
04/16/2017  03:53 PM               570 HellowWorld10.java
               2 File(s)            804 bytes
               0 Dir(s)  22,762,598,400 bytes free

It changed the directory where the java program is there.

And displayed the files.

Let us see the next output:

D:\JavaSamples\Javatest>javac HellowWorld.java 
'javac' is not recognized as an internal or external command,
operable program or batch file.

It shows error for java path. Jenkins is not recognizing the path. The javac [compiler application is in the below path: D:\Java\jdk-9.0.1\bin ]

Javac-path.png

Now, this need to be corrected in the project.
To correct this we need to goto option: “Configure”.

Open it into project window to update some more commands.

I have updated the command window with the below commands:
cd \JavaSamples\Javatest
dir hellow*.java
del HellowWorld.class
dir hellow*.java
D:\Java\jdk-9.0.1\bin\javac HellowWorld.java
dir HellowWorld.*
java HellowWorld

Now, let me run the job by using “Build now option”.

For debugging purpose, I have executed this job some more times. Hence history shows multiple builds on it.

Our current build is #5. And let us open it and see the console output:

Jenkins-Project-vskumar2017test1-buildsNow#5

The console output shows as below:

Jenkins-Project-vskumar2017test1-console#5

Now you can see the whole console output as below in text format:

Console Output
Started by user Vskumar2017
Building in workspace D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1
[vskumar2017test1] $ cmd /c call C:\WINDOWS\TEMP\jenkins1398066858541735603.bat

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd
D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd \JavaSamples\Javatest

D:\JavaSamples\Javatest>dir hellow*.java
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

04/16/2017 03:52 PM 234 HellowWorld.java
04/16/2017 03:53 PM 570 HellowWorld10.java
2 File(s) 804 bytes
0 Dir(s) 22,761,955,328 bytes free

D:\JavaSamples\Javatest>del HellowWorld.class

D:\JavaSamples\Javatest>dir hellow*.java
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

04/16/2017 03:52 PM 234 HellowWorld.java
04/16/2017 03:53 PM 570 HellowWorld10.java
2 File(s) 804 bytes
0 Dir(s) 22,761,955,328 bytes free

D:\JavaSamples\Javatest>D:\Java\jdk-9.0.1\bin\javac HellowWorld.java

D:\JavaSamples\Javatest>dir HellowWorld.*
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

11/17/2017 12:3

9 PM 427 HellowWorld.class
04/16/2017 03:52 PM 234 HellowWorld.java
2 File(s) 661 bytes
0 Dir(s) 22,761,955,328 bytes free

D:\JavaSamples\Javatest>java HellowWorld
Hello World

D:\JavaSamples\Javatest>exit 0
Finished: SUCCESS

=======================>
Observe there was no error displayed as we have given the correct javac application path.

Now I have updated the commands as below to remove the existing HellowWorld.class file.
cd
cd \JavaSamples\Javatest
dir hellow*.*
echo ‘Assuming .class file is already there..”
del HellowWorld.class
dir hellow*.java
D:\Java\jdk-9.0.1\bin\javac HellowWorld.java
dir HellowWorld.*
java HellowWorld
=======================>
You can see the output under build#7:
========================>

Console Output
Started by user Vskumar2017
Building in workspace D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1
[vskumar2017test1] $ cmd /c call C:\WINDOWS\TEMP\jenkins7100481173282587024.bat

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd
D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1

D:\Jenkins\Jenkins 2.9\workspace\vskumar2017test1>cd \JavaSamples\Javatest

D:\JavaSamples\Javatest>dir hellow*.*
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

11/17/2017 12:45 PM 427 HellowWorld.class
04/16/2017 03:52 PM 234 HellowWorld.java
04/16/2017 03:53 PM 570 HellowWorld10.java
3 File(s) 1,231 bytes
0 Dir(s) 22,760,976,384 bytes free

D:\JavaSamples\Javatest>echo ‘Assuming .class file is already there..”
‘Assuming .class file is already there..”

D:\JavaSamples\Javatest>del HellowWorld.class

D:\JavaSamples\Javatest>dir hellow*.java
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

04/16/2017 03:52 PM 234 HellowWorld.java
04/16/2017 03:53 PM 570 HellowWorld10.java
2 File(s) 804 bytes
0 Dir(s) 22,760,976,384 bytes free

D:\JavaSamples\Javatest>D:\Java\jdk-9.0.1\bin\javac HellowWorld.java

D:\JavaSamples\Javatest>dir HellowWorld.*
Volume in drive D is New Volume
Volume Serial Number is 5C67-6F04

Directory of D:\JavaSamples\Javatest

11/17/2017 12:47 PM 427 HellowWorld.class
04/16/2017 03:52 PM 234 HellowWorld.java
2 File(s) 661 bytes
0 Dir(s) 22,760,976,384 bytes free

D:\JavaSamples\Javatest>java HellowWorld
Hello World

D:\JavaSamples\Javatest>exit 0
Finished: SUCCESS
=================================>
Now, you can see message display from echo command.
And the old class file is removed and the new file time stamp can be seen differently.

Now, how to make failure a job ?:

Please see the screen display with a failed job:

Jenkins-vskumar2017-success1

Now, let us see the console output:

Console-output-vskumar2017-3.png

In this example I have given a wrong file name to execute. Hence it is failed.
It checks the last commands results. You can change them and cross check as an exercise.
The failure error flag also it shows as “1”.
When the job was success the flag showed as “0”.

Hope you understand the difference between failure and success of Jenkins build.
So, we need to make sure the commands/script mentioned in the command window should be a debugged one. Then the jobs success can be seen.

Please note;
If it is not a recognized command as an internal or external command,
operable program or batch file. Jenkins will not count it as a failure.

Exercise:
Take a new Java program and create a job to compile and run it.

How to use My views:
You can see the build history in graphical format as below with My views option:

Jenkins-Job-Views

 

At this point with this blog I want to close now, with the above scenarios.

You can also see:

https://www.youtube.com/edit?o=U&video_id=lciTHyxCgfE

 

Feel free to contact for any support:

Vcard-Shanthi Kumar V-v3

 

Advertising3.pngFor Intended DevOps Engineers: We also train freshers [limited people] on Agile & Scrum concepts to till DevOps practices and  CDI automation [with tools]. Interested candidates can contact by e-mail/phone to join or book your seat in Bangalore.

For Employers: If you are planning to accelerate your DevOps practices from Agile & Scrum onwards, we can do resourcing for you [in Bangalore]. Please contact for details.

If you are DevOps practices:

https://vskumar.blog/2018/10/17/join-devops-practices-group-on-fb/

 

 

Why the DevOps Practice is mandatory for an IT Employee

DevOps Patterns
devops-process
  1. DevOps is a terminology used to refer to a set of principles and practices to emphasize the collaboration and communication of Information Technology [IT] professionals in a software project organization, while automating the process of software delivery and infrastructure using Continuous Delivery Integration[CDI] methods.
  2. The DevOps is also connecting the teams of Development and Operations together to work collaboratively to deliver the Software to the customers in an iterative development model by adopting Continuous Delivery Integration [CDI] concepts. The software delivery happens  in small pieces at different delivery intervals. Sometimes these intervals can be accelerated depends on the customer demand.
  3. The DevOps is a new practice globally adopted by many companies and its importance and implementation is accelerating by maintaining constant speed.  So every IT professional need to learn the concepts of DevOps and its Continuous Delivery Integration [CDI] methods. To know the typical DevOps activities by role just watch the video: https://youtu.be/vpgi5zZd6bs, it is pasted below in videos.
  4. Even a college graduate or freshers also need to have this knowledge or practices to work closely with their new project teams in a company. If a fresher attends this course he/she can get into the project shoes faster to cope up with the  experienced teams.
  5. Another way; The DevOps is an extension practice of Agile and continuous delivery. To merge into this career; the IT professionals  need to learn the Agile concepts, Software configuration management, Release management, deployment management and  different DevOps principles and practices to implement the CDI patterns. The relevant tools for these practices integration. There are various tool vendors in the market. Also open source tools are very famous. Using these tools the DevOps practices can be integrated to maintain the speed for CDI.
  6. There  are tools related with version control and CDI automation. One need to learn the process steps related to these areas by attending a course. Then the tools can be understood easily.  If one understands these CDI automation practices and later on learning the tools process is very easy by self also depends on their work environment.
  7. As mentioned in the above; Every IT company or IT services company need to adopt the DevOps practices for their customers competent service delivery in global IT industry. When these companies adopt these practices, their resources also need to be with thorough knowledge of DevOps practices to serve to the customers. The companies can get more benefit by having these knowledged resources. At the same time the new joinees in any company either experienced or fresher professional if they have this knowledge, their CTC in view of perks will be offered more or with competent offer they may be invited to join in that company.
  8. Let us know if you need  DevOps training  from  the IT industry experienced people; which includes the above practice areas to boost you in the IT industry.

Training will be given by 3 decades of Global IT experienced  professional(s):

https://www.linkedin.com/in/shanthi-kumar-v-itil%C2%AE-v3-expert-devops-istqb-752201a/

Watch the below videos on why the IT company need to shift to DevOps work culture and practices and what advantages the company can get and the employees can get :

For DevOps roles and activities watch my video:

Folks, I also run the DevOps Practices Group: https://www.facebook.com/groups/1911594275816833/?ref=bookmarks

There are many Learning units I am creating with basics. If you are not yet a member, please apply to utilize them. Read and follow the rules before you click your mouse.

For contact/course details please visit:

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SDLC & Agile – Interview questions for Freshers -5

In continuation of my previous blog  on this subject following questions and answers are continued:

1. What is retrospective in agile and where it can be useful?

Ans: During agile development model in each iteration different requirements are considered to design, develop and construct the code. While performing these tasks there can be different issues identified and resolved by the teams at each stage. The teams need to maintain knowledge information against to each issue as lessons learnt. These issues resolution mechanism processes are going to be considered for any process improvements  for next iteration. During the retrospective [after completing iteration] the team is going to discuss the lessons learnt  from the completed  iteration and the best practices  identified for next iteration. The retrospective is a mandatory activity for every iteration of Agile projects. And this need to be conducted before starting the next iteration.

 

2.   What is continuous stream of development in agile model?

Ans: As per the agile concept continuous software delivery need to  happen by following iterative development. Let us assume the development team consider the four days for development and fifth day it need to go for release and deployment, fifth day onwards developer considered as other iteration/SPRINT as their continuous development activity. The developers are picking up one  by one SPRINT items for their construction activity this is called as continuous stream of development. When the testing activity is ongoing the developer can pickup other workable items from the SPRINT to do construction activity.

 

3. What is Continuous Delivery[CD] in Agile ?

Ans: As per the agile concepts and principles, the developer need to get small chunk of workable item only which can be delivered in hours or few days.  When this kind of continuous development is happening through the agile developers there will be builds for continuous testing and deployments. Obviously then the agile project leads to have continuous  delivery [CD] of software into production with small chunks of functionality or fixes.

Example: Many technology companies consider each SPRINT item to complete in hours only to speed up their ongoing software deployments for their daily business needs. This kind of concept is called as Continuous Delivery [CD] in Agile.

 

4.  What is transition activity and their tasks involved in  agile project?

Ans:  Transition activity is start with deploying software release into production. Once the software construction phase is signed off the transition activity need to be started, typically transition activity contains following tasks.

i) Active stakeholder participation

ii) Final system testing

iii) Final acceptance testing

iv) Finalize documentation

v) Final testing of the release

vi) Train end users

vii) Train production staff

viii) Deploy into production.

All the above tasks are performed in the sequential order.

 

5.  What is final system testing during transition stage?

Ans: Once software can be deployed  internally, the planned system testing need to be conducted by testing team for a specific iteration. Once system testing is passed or certified the  acceptance testing need to be started.

 

 6.  When can you conduct final acceptance testing in agile model?

Ans:  In any agile project developers need to conduct a skeleton software demo to the users. Depends on the design requirement once users approved it, the Construction phase need to be  started. Once the software is constructed and  it can be deployed internally for various levels of testing during the transition stage of agile project. At this stage the software release is deployed in test environment. Then the  system testing is conducted and signed off.  The final acceptance testing is conducted on the software to be delivered to the users in production. Once the final acceptance is signed off the remaining tasks are being performed during transition phase, as mentioned in the list of tasks.

 

7. When can the pilot testing  happen and who all will perform it?

Ans: During the transition stage once the acceptance test is signed off , and final document is done, the software build is executed under a pilot test in a preproduction test or in a production environment depends on the organization policy. The pilot test is attended by the business users and testers or nominated coordinator along with the development team and operations[ops] team.

 

8.  During the transition stage who all need to be trained?

Ans:  Once the pilot test is done software end users and the production staff (ops team) needs to be trained to operate the product in live [production] for business operations.

 

9.  When can you deploy the system into production?

Ans: During transition stage once the pilot test is signed off, end users and production staff will be trained on software system and then it is deployed into production.

 

10. How a  prototype can be designed ?

Ans: When the business user give some requirements which consists of user interface and some data processing to provide output, there are two ways we can design prototype software; a) Prototype model  b) Design and developing the complete software.

a) Prototype model: During prototype model developer design and develop the critical requirements of the users and demonstrate those things as the skeleton software. The skeleton software will not have the complete software operations. It will have an user interface to get an idea by the user on the software to be delivered by the development in future. Once user approved skeleton model, developer can design complete model through Agile SDLC. Note; the prototype model or process can be applied  for one or more SPRINT cycles or iterations.

b) Design and developing the complete software: This kind of software happens in a regular Agile project process from collection of user story onwards. All the agile phases and their tasks will be applied for execution. If the team agreed to a demo [for prototype], the user demos can also happen as and when required for each SPRINT during construction phase.

Keep watching this site for further updates.

Contact for any guidance/coaching.

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Continuous test automation planning during Agile iterations

Continuous test automation planning during Agile iterations

Please refer to my blog and videos on Agile practices and the importance of Re-usable code libraries for cycle time reduction.

During the reusable code usage and the iterations or sprint planning, the test automation also can be planned, designed and implemented.

This blog eloborates on  the easy processes can be used to implement it and demonstrate the cycle time reduction. Please note atleast after passing the two cycles of tests on the selected manual scripts need to be planned for test automation.

I am trying to elaborate on the process of the Automation of unit testing and component or module integration test automation. Please note the test automation is also a development project. Hence some of the phases are similar to SDLC. The pictorial chart elaborates the detailed steps involved in these test phases automation. Module (Unit) or Component Development in Agile: The below contents and the chart narrates the relationship of automation Development process and the Testing process under each development phase. Development and Testing process Relationship table:

Phase Development Process Test Process
Module (Unit) or component Development Design module from requirements Perform test planning and test environment set up.
  Code module Create test design and develop test data.
  Debug module Write test scripts or record test scenario using module.
  Unit test module Debug automated test script by running against module. Also, tools that support unit testing [Purify, etc] can be used.
  Correct defects Rerun automated test script to regression test as defects are corrected.
  Conduct Performance Testing Verify system is scaleable and will meet the performance requirements. This is the entry criteria for Integration test automation.
Integration
Build system by connecting modules.Conduct Integration test with connected modules.Review trouble reports. Combine unit test scripts and add new scripts that demonstrate module inter-connectivity. Use test tool to support automated integration testing.
  Correct defects and update defect status. Rerun automated test script as part of regression test, as defects are corrected.
  Continued Performance Testing Activities At this point, Verifying system is scaleable and will meet performance requirements with the integrated modules. If this passes then the system test or VVT entry can be considered.

Below chart demsontrates the process steps to be used for test automation of unit test and integration testing:

UT&IT

The acronyms used in the chart: TC–>Test case, TD–>Test data, TR–> Test requirement, UT–>Unit test, IT–> Integration test.

All the automated test scripts and test data  need to be preserved under configuration management tools.

Choosing the right tools for test automation comes under tools evaluation process. Once the tools are identified, the above processes can be planned and adopted for regular practice on the Agile projects.

 

 

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How to Reduce Agile cycle time with reusable code ? [with Video lessons] # Kindle

Agile practices and the importance of Re-usable code libraries for cycle time reductionReusable code usage for Agile iterations planning by examples:

In many Agile transformation sessions the Agile practitioners or savvy’s discuss more on the process related activities rather than elaborating on the technical or software engineering process steps to reduce the cycle time.

At the same time prior to the Agile meetings, activity efforts need to be defined by the designers and the developers. Unless they identify the size of the reusable code components in the applications it is not worth for conducting the Release or Sprint planning meetings for planning of the iterations.

Hence it is the moral responsibility of the technical teams to apply this kind of practices ahead of Agile process or Scrum meetings.

If you are interested to know what reusable code with examples is, this E-Book can be useful. Using this technique, you can plan for code refractor and its cleaning also to get ROI on future Agile iterations. During Scrum meetings, these are the important topics where technical people need to discuss for customer’s ROI acceleration planning and also the cycle time reduction acceleration. The team’s technical capabilities also can be accelerated by following these practices regularly.

I have considered an application example of E-commerce site building for defining the Sprint planning and their iterations. Each iteration has been divided into different reusable code components design parts.

The relevant graphics have been designed and added into this E-book. The software configuration processes with Code Items process have been discussed also.

One can answer the following after understanding this E-Book content:
How to define the reusable code?
How the Iterations can be planned?
Is it possible to demonstrate the iterations cycle time reduction?
What are the entry criteria for Sprint planning?
What are the jumpstart activities required for designers before Agile release meeting?
How to manage the code components with configuration management process?
How to plan the efforts reduction for Sprint cycles?

The proposed or mandatory readers are:
Agile developers
Agile Designers
Agile PMS
Agile Product Owners
Agile teams
Who all intended to learn Agile Practices?

It is cheaper now, please visit: http://www.amazon.com/Technical-best-practices-reusable-iterations-ebook/dp/B012CHK20Q/ref=sr_1_10?ie=UTF8&qid=1452047932&sr=8-10&keywords=Shanthi+Vemulapalli

Reusable-code-Cover1-Pixels

 

 

 

 

 

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Visit for Agile interview questions:

https://vskumar.blog/2017/09/04/sdlc-agile-interview-questions-for-freshers-1/

Visit for DevOps FAQs:

Devops-practices-faqs-1

 

https://vskumar.blog/2017/10/14/typical-devops-roles-and-activities/