Category Archives: Continuous Delivery Integration

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

31. DevOps: Jenkins-How to use Backup/Restore using thinbackup plugin ?

\]jenkins

Through this video I have demonstrated the below steps using Jenkins and its thinkbackup plugin process/usage.

=== Steps used in video ====>

How to take jenkins backup ?
1. You need to configure the thinbackup plugin.
2. Search for that plugin in
Manage Jenkins option.
3. Click on Available tab. It shows the locally
available plugins.
4. Then goto filter and type the plugin name as
thinbackup.
5. Now let us check it. You can see the icon,
it is installed.
6. Once you have this, you can explore it.
7. Please note you also need to configure
Restore.
8. Now, let us configure the backup.
After that we can use backupnow option to
take a backup. It stores on the given path.
So, we should use settings.
9. Now, let us test one backup …
10. Let us check the backup file…
11. Observe the created jobs are there…
12. Now, let me run a build..
13.Created 8th Build.
14. Now let me take the new backup…
15. Now, let me use restore to restore
the past build.
16.See the current build history …
17. I am picking up the 1st it was
made in the beginning…
18. Now, let us verify the jenkins
system jobs/builds.
19. It is overwritten on the existing jobs..
20. Let us delete some jobs and restore
the 8thbuild backup.
21. Let me try to restore the latest backup
which has the 8thbuild …
22. Let us restart the server to use the
latest restore …. Let me pause you …
23. It is ready to login … let us test it..
24. Please Note;
When restored it unzipped and kept the files.
When we restarted the jenkins server
it pickedup those files only.
We can see the 8th build is there.
25. From this exercise and trouble shoot,
we can conclude:
i) We need to use thinbackup plugin to
setup backup/restore process.
ii. Initially we use backup plugin and
later we can setup restore setup after
configuring the backup options.

iii. And when we restore a particular build
we need to restart the jenkins server.
That is all for this exercise..

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

 

Advt-course3rd page

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

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`/yho:` -yd.
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`.—–+/.` `.-+hh/` `od. NMMNmds/ `mmy:` +mMy `:yy.
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.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/

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]
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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]
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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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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

 

 

9. DevOps: How to do Containers housekeeping ?

Docker-logo

In  continuation of my previous blog on “8. DevOps:How to control and operate docker containers”, in this blog I would like to show some lab practice on “docker Containers housekeeping”.

From the previous lab sessions, we have seen many containers when we used ps -a option.

We have used two containers most of the times.

Others are not required. This time we will see how to remove a container physically.

Let us consider the below containers to remove using rm command:

32bc16b508d4        ubuntu 
a744246ffb8e        hello-world
1dd55efde43f        hello-world

$sudo docker rm 1dd55efde43f 
$sudo docker rm a744246ffb8e 
$sudo docker rm 32bc16b508d4 
================ You can see the above three containers are removed =========>
vskumar@ubuntu:~$ sudo docker rm 1dd55efde43f 
1dd55efde43f
vskumar@ubuntu:~$ sudo docker rm a744246ffb8e 
a744246ffb8e
vskumar@ubuntu:~$ sudo docker rm 32bc16b508d4 
32bc16b508d4
vskumar@ubuntu:~$ sudo docker ps -a |more
CONTAINER ID        IMAGE               COMMAND                 CREATED         
    STATUS                         PORTS               NAMES
f123dbd09116        ubuntu:16.04        "/bin/bash"             18 minutes ago  
    Exited (0) 18 minutes ago                          elastic_nightingale
3cfdea29ce6e        ubuntu              "bash"                  27 minutes ago  
    Exited (0) 26 minutes ago                          gallant_nobel
155f4b0764b1        ubuntu:16.04        "/bin/bash"             About an hour ag
o   Exited (0) 12 minutes ago                          zen_volhard
11e293722c64        ubuntu:16.04        "/bin/bash"             About an hour ag
o   Exited (0) About an hour ago                       dreamy_bassi
d10ad2bd62f7        ubuntu:16.04        "/bin/bash"             About an hour ag
o   Exited (0) About an hour ago                       cranky_dijkstra
cb1ff260d48e        ubuntu              "ls /usr/src"           11 hours ago    
    Exited (0) 11 hours ago                            wonderful_hawking
b20691fd8fb5        ubuntu              "ls /usr"               11 hours ago    
    Exited (0) 11 hours ago                            friendly_mirzakhani
431ba4c53028        ubuntu              "ls"                    11 hours ago    
    Exited (0) 28 minutes ago                          affectionate_nobel
2c31684bb1f4        ubuntu              "ls -la"                11 hours ago    
    Exited (0) 11 hours ago                            zealous_meitner
fe2e3b449daf        ubuntu              "ls -la /home/."        11 hours ago    
    Exited (0) 11 hours ago                            dreamy_shirley
c44bdd05b94d        ubuntu              "ls -la home."          11 hours ago    
    Exited (2) 11 hours ago                            elastic_pasteur
8b8afa82859a        ubuntu              "ls -la"                11 hours ago    
    Exited (0) 11 hours ago                            festive_panini
2811eb37af61        ubuntu              "ls -la 604831dbce2a"   11 hours ago    
    Exited (2) 11 hours ago                            jolly_swartz
604831dbce2a        ubuntu:16.04        "/bin/bash"             11 hours ago    
    Exited (0) 11 hours ago                            vibrant_ride
718636415a7f        ubuntu:16.04        "/bin/bash"             12 hours ago    
    Exited (0) 12 hours ago                            reverent_noyce
53a7751d4673        ubuntu:16.04        "/bin/bash"             13 hours ago    
    Exited (0) 13 hours ago                            musing_chandrasekhar
1ba71598b7b8        hello-world         "/hello"                16 hours ago    
    Exited (0) 16 hours ago                            musing_kare
vskumar@ubuntu:~$  
==============>
Now let us consider some more examples  as below:
3cfdea29ce6e        ubuntu 
cb1ff260d48e        ubuntu 
b20691fd8fb5        ubuntu 
431ba4c53028        ubuntu 
c31684bb1f4        ubuntu 
2c31684bb1f4        ubuntu 
fe2e3b449daf        ubuntu
c44bdd05b94d        ubuntu 
2811eb37af61        ubuntu
Now, let us use the below rm commands:
$sudo docker rm 3cfdea29ce6e
$sudo docker rm cb1ff260d48e
$sudo docker rm b20691fd8fb5 
$sudo docker rm 431ba4c53028 
$sudo docker rm 2c31684bb1f4
$sudo docker rm fe2e3b449daf 
$sudo docker rm c44bdd05b94d
$sudo docker rm 2811eb37af61
=================>
See the below output also:
 ================== Container removal ==========>
vskumar@ubuntu:~$ clear

vskumar@ubuntu:~$ sudo docker rm 3cfdea29ce6e
3cfdea29ce6e
vskumar@ubuntu:~$ sudo docker rm cb1ff260d48e
cb1ff260d48e
vskumar@ubuntu:~$ sudo docker rm b20691fd8fb5
b20691fd8fb5
vskumar@ubuntu:~$ sudo docker rm 431ba4c53028
431ba4c53028
vskumar@ubuntu:~$ sudo docker rm 2c31684bb1f4
2c31684bb1f4
vskumar@ubuntu:~$ sudo docker rm fe2e3b449daf
fe2e3b449daf
vskumar@ubuntu:~$ sudo docker rm fc44bdd05b94d
Error: No such container: fc44bdd05b94d
vskumar@ubuntu:~$ sudo docker rm c44bdd05b94d
c44bdd05b94d
vskumar@ubuntu:~$ sudo docker rm 2811eb37af61
2811eb37af61
vskumar@ubuntu:~$ 
==========================>
Now we can see the list of available containers:
============= List of latest containers ==============>
vskumar@ubuntu:~$ sudo docker ps -a |more
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                         PORTS               NAMES
f123dbd09116        ubuntu:16.04        "/bin/bash"         28 minutes ago      Exited (0) 28 minutes ago                          elastic_nigh
tingale
155f4b0764b1        ubuntu:16.04        "/bin/bash"         About an hour ago   Exited (0) 22 minutes ago                          zen_volhard
11e293722c64        ubuntu:16.04        "/bin/bash"         About an hour ago   Exited (0) About an hour ago                       dreamy_bassi
d10ad2bd62f7        ubuntu:16.04        "/bin/bash"         2 hours ago         Exited (0) About an hour ago                       cranky_dijks
tra
8b8afa82859a        ubuntu              "ls -la"            11 hours ago        Exited (0) 11 hours ago                            festive_pani
ni
604831dbce2a        ubuntu:16.04        "/bin/bash"         12 hours ago        Exited (0) 11 hours ago                            vibrant_ride
718636415a7f        ubuntu:16.04        "/bin/bash"         12 hours ago        Exited (0) 12 hours ago                            reverent_noy
ce
53a7751d4673        ubuntu:16.04        "/bin/bash"         13 hours ago        Exited (0) 13 hours ago                            musing_chand
rasekhar
1ba71598b7b8        hello-world         "/hello"            16 hours ago        Exited (0) 16 hours ago                            musing_kare
vskumar@ubuntu:~$ 
===========================>
Now, I wan to keep very few containers only and remove the below containers:

604831dbce2a        ubuntu:16.04
718636415a7f        ubuntu:16.04 
53a7751d4673        ubuntu:16.04
8b8afa82859a        ubuntu 
I want to use the below  commands to remove  the above containers:
$sudo docker rm 604831dbce2a
$sudo docker rm 718636415a7f
$sudo docker rm 53a7751d4673
$sudo docker rm 8b8afa82859a

========================= We can see the latest/limited containers =======>
vskumar@ubuntu:~$ sudo docker rm 604831dbce2a
604831dbce2a
vskumar@ubuntu:~$ sudo docker rm 718636415a7f
718636415a7f
vskumar@ubuntu:~$ sudo docker rm 53a7751d4673
53a7751d4673
vskumar@ubuntu:~$ sudo docker rm 8b8afa82859a
8b8afa82859a
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                         PORTS               NAMES
f123dbd09116        ubuntu:16.04        "/bin/bash"         36 minutes ago      Exited (0) 36 minutes ago                          elastic_nightingale
155f4b0764b1        ubuntu:16.04        "/bin/bash"         About an hour ago   Exited (0) 30 minutes ago                          zen_volhard
11e293722c64        ubuntu:16.04        "/bin/bash"         About an hour ago   Exited (0) About an hour ago                       dreamy_bassi
d10ad2bd62f7        ubuntu:16.04        "/bin/bash"         2 hours ago         Exited (0) About an hour ago                       cranky_dijkstra
1ba71598b7b8        hello-world         "/hello"            16 hours ago        Exited (0) 16 hours ago                            musing_kare
vskumar@ubuntu:~$ sudo docker ps 
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
vskumar@ubuntu:~$ 
================================>
We can also see the current container ids as below:
========== Listing containers ids ===============>
vskumar@ubuntu:~$ sudo docker ps -aq
f123dbd09116
155f4b0764b1
11e293722c64
d10ad2bd62f7
1ba71598b7b8
vskumar@ubuntu:~$ 
===============================>
To remove the inactive containers there is a prune command. Let us try with it.
Before doing it I want to make a container active and try this prune command on it:
================= I have made one container Active ======>
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                         PORTS               NAMES
f123dbd09116        ubuntu:16.04        "/bin/bash"         About an hour ago   Exited (0) About an hour ago                       elastic_nightingale
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Exited (0) 40 minutes ago                          zen_volhard
11e293722c64        ubuntu:16.04        "/bin/bash"         2 hours ago         Exited (0) 2 hours ago                             dreamy_bassi
d10ad2bd62f7        ubuntu:16.04        "/bin/bash"         2 hours ago         Exited (0) 2 hours ago                             cranky_dijkstra
1ba71598b7b8        hello-world         "/hello"            17 hours ago        Exited (0) 17 hours ago                            musing_kare
vskumar@ubuntu:~$ sudo docker start 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps 
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up 6 seconds                            zen_volhard
vskumar@ubuntu:~$ 
========================>
To use prune , below format should be used:
$ sudo docker container prune
=========== The usage of prune command =======>
vskumar@ubuntu:~$ 
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:
f123dbd09116561a042e12060f449daa9a36d9a59034b1dd1b96846e66ead14d
11e293722c646a0def7a8a1f2cdf85a47654eb62ef7701bd2d7221c7e69a943f
d10ad2bd62f7a8de379272f21dfccec89c0e5829b3a58ce01927530b6b44ea01
1ba71598b7b8d97fcbd3a589a6665238690be99936b6782647b5040eeb82aafa
Total reclaimed space: 844B
vskumar@ubuntu:~$ 
========== You can see the removed container ids =============>
You can see the existing  containers:
====== Available containers after Housekeeping is done =========>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up 6 minutes                            zen_volhard
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         2 hours ago         Up 6 minutes                            zen_volhard
vskumar@ubuntu:~$ sudo docker ps -aq
155f4b0764b1
vskumar@ubuntu:~$
===================>
In this exercise we have seen the housekeeping of containers well.
Please note if you have deleted all the containers by mistake, you need to install the containers again. 
Follow the containers creation exercise.

I would like to break this session at this point. In the next blog I would like to present the lab practice on:

 “How to Build images from Docker containers?

Vcard-Shanthi Kumar V


					

8. DevOps:How to control and operate docker containers

Docker-logo

In  continuation of my previous blog on “7. DevOps: How to track changes in a container”, in this blog I would like to show some lab practice “How to control and operate docker containers”.

Controlling/operating Docker container:

In this exercise initially, we can see on how to start/stop/restart the containers.

The Docker Engine enables us to start, stop, and restart a container with a set of docker subcommands.

Let me display the docker images:

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

vskumar@ubuntu:~$ 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 15:09:35 PST; 2min 24s ago

Docs: https://docs.docker.com

Main PID: 1356 (dockerd)

Tasks: 30

Memory: 95.2M

CPU: 3.998s

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

vskumar@ubuntu:~$ sudo docker images

REPOSITORY TAG IMAGE ID CREATED SIZE

hello-world latest f2a91732366c 4 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:~$

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

Now, I want to launch our container ubuntu 16.04 with start subcommand and experiment with the docker stop subcommand, as given below:

$ sudo docker run -i -t ubuntu:16.04 /bin/bash

======================>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker run -i -t ubuntu:16.04 /bin/bash
root@d10ad2bd62f7:/# 
======================>
Now, we are with this container in interactive mode.
Let us apply some linux commands as below:
========================>
root@d10ad2bd62f7:/# pwd
/
root@d10ad2bd62f7:/# ls
bin   dev  home  lib64  mnt  proc  run   srv  tmp  var
boot  etc  lib   media  opt  root  sbin  sys  usr
root@d10ad2bd62f7:/# cd home
root@d10ad2bd62f7:/home# ls
root@d10ad2bd62f7:/home# cd ../var
root@d10ad2bd62f7:/var# ls
backups  cache  lib  local  lock  log  mail  opt  run  spool  tmp
root@d10ad2bd62f7:/var# cd tmp
root@d10ad2bd62f7:/var/tmp# pwd
/var/tmp
root@d10ad2bd62f7:/var/tmp# ls
root@d10ad2bd62f7:/var/tmp# cd ../lib
root@d10ad2bd62f7:/var/lib# ls
apt  dpkg  initscripts  insserv  misc  pam  systemd  update-rc.d  urandom
root@d10ad2bd62f7:/var/lib# 
================================>

Now I want to create a file as below in this container:
==================>

root@d10ad2bd62f7:/var/lib# pwd
/var/lib
root@d10ad2bd62f7:/var/lib# cd ../../home
root@d10ad2bd62f7:/home# ls
root@d10ad2bd62f7:/home# touch file1.txt
===================>

Let me add some text into this file as below:
==========>
root@d10ad2bd62f7:/home# echo " Testing containers " > file1.txt
root@d10ad2bd62f7:/home# echo " Applying stop command on containers " > file1.txt
root@d10ad2bd62f7:/home# cat file1.txt
 Applying stop command on containers 
root@d10ad2bd62f7:/home# echo " Testing containers " > file1.txtroot@d10ad2bd62f7:/home# echo " Applying stop command on containers " >> file1.txt
root@d10ad2bd62f7:/home# ls
file1.txt
root@d10ad2bd62f7:/home# ls -l
total 4
-rw-r--r-- 1 root root 59 Nov 25 23:20 file1.txt
root@d10ad2bd62f7:/home# cat file1.txt 
Testing containers 
Applying stop command on containers 
root@d10ad2bd62f7:/home# 
===============>

I have applied some more linux file operations on this container as below:
=================>
root@d10ad2bd62f7:/home#      
root@d10ad2bd62f7:/home# cat file1.txt >> file2.txt
root@d10ad2bd62f7:/home# ls
file1.txt  file2.txt
root@d10ad2bd62f7:/home# ls -l
total 8
-rw-r--r-- 1 root root 59 Nov 25 23:20 file1.txt
-rw-r--r-- 1 root root 59 Nov 25 23:22 file2.txt
root@d10ad2bd62f7:/home# diff file1.txt file2.txt
root@d10ad2bd62f7:/home# echo " Applying restart command also on containers " >> file1.txt
root@d10ad2bd62f7:/home# ls -l
total 8
-rw-r--r-- 1 root root 105 Nov 25 23:23 file1.txt
-rw-r--r-- 1 root root  59 Nov 25 23:22 file2.txt
root@d10ad2bd62f7:/home# diff file1.txt file2.txt3d2
<  Applying restart command also on containers 
root@d10ad2bd62f7:/home# 
====================>
Now, let me apply a stop command on this container and see as 
below by using exit to come out and stop:
=====================>
root@155f4b0764b1:/# 
root@155f4b0764b1:/# exit
exit
vskumar@ubuntu:~$ sudo docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
hello-world         latest              f2a91732366c        4 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:~$ sudo docker stop  d10ad2bd62f7
d10ad2bd62f7
vskumar@ubuntu:~$ 
=============>
Now, I want to check the containers status using ps -a command as below:
==============>
vskumar@ubuntu:~$ sudo docker ps -a
CONTAINER ID        IMAGE               COMMAND                 CREATED             STATUS                     PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"             2 minutes ago       Exited (0) 2 minutes ago                       zen_volhard
cb1ff260d48e        ubuntu              "ls /usr/src"           10 hours ago        Exited (0) 10 hours ago                        wonderful_hawking
b20691fd8fb5        ubuntu              "ls /usr"               10 hours ago        Exited (0) 10 hours ago                        friendly_mirzakhani
431ba4c53028        ubuntu              "ls"                    10 hours ago        Exited (0) 10 hours ago                        affectionate_nobel
2c31684bb1f4        ubuntu              "ls -la"                10 hours ago        Exited (0) 10 hours ago                        zealous_meitner
fe2e3b449daf        ubuntu              "ls -la /home/."        10 hours ago        Exited (0) 10 hours ago                        dreamy_shirley
c44bdd05b94d        ubuntu              "ls -la home."          10 hours ago        Exited (2) 10 hours ago                        elastic_pasteur
8b8afa82859a        ubuntu              "ls -la"                10 hours ago        Exited (0) 10 hours ago                        festive_panini
2811eb37af61        ubuntu              "ls -la 604831dbce2a"   10 hours ago        Exited (2) 10 hours ago                        jolly_swartz
604831dbce2a        ubuntu:16.04        "/bin/bash"             10 hours ago        Exited (0) 10 hours ago                        vibrant_ride
718636415a7f        ubuntu:16.04        "/bin/bash"             11 hours ago        Exited (0) 10 hours ago                        reverent_noyce
53a7751d4673        ubuntu:16.04        "/bin/bash"             12 hours ago        Exited (0) 12 hours ago                        musing_chandrasekhar
32bc16b508d4        ubuntu              "bash"                  13 hours ago        Exited (0) 13 hours ago                        eager_goldberg
1dd55efde43f        hello-world         "/hello"                13 hours ago        Exited (0) 13 hours ago                        peaceful_pasteur
a744246ffb8e        hello-world         "/hello"                15 hours ago        Exited (0) 15 hours ago                        naughty_wing
1ba71598b7b8        hello-world         "/hello"                15 hours ago        Exited (0) 15 hours ago                        musing_kare
vskumar@ubuntu:~$ 
===================>
you can see the latest status of our container;
155f4b0764b1        ubuntu:16.04        "/bin/bash"             2 minutes ago       Exited (0) 2 minutes ago                       zen_volhard
It means Docker  maintains in the logs on the usage of containers also.
Now, I want to start the previously stopped container using the docker start subcommand 
by specifying the container ID as an argument, as follows:
$ sudo docker start 155f4b0764b1
===============>
vskumar@ubuntu:~$ sudo docker start 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ 
===============>
Let us check the images status also as below:
==================> Copied the 1st two lines only ----->
vskumar@ubuntu:~$ sudo docker ps -a |more
CONTAINER ID        IMAGE               COMMAND                 CREATED         
    STATUS                      PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"             10 minutes ago  
    Up About a minute                               zen_volhard
11e293722c64        ubuntu:16.04        "/bin/bash"             12 minutes ago  
    Exited (0) 12 minutes ago  
====================>
It means it shows the current status of the container id:155f4b0764b1 
We need to notice one thing here.

By default, the docker start subcommand will not attach to the container.

We can attach it to the container either using the -a option in the docker start subcommand or by explicitly using the docker attach subcommand.

Now let us try these options.

We will see attach command

$ sudo docker attach 155f4b0764b1
=================>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker attach 155f4b0764b1
root@155f4b0764b1:/# 
root@155f4b0764b1:/#
=================>
So the attach command brought the container into interactive mode.
Now let me exit it and try the -a option with docker start command:
==================>
root@155f4b0764b1:/home# 
root@155f4b0764b1:/home# exit
exit
===============>
with start -a option:
=============>
vskumar@ubuntu:~$ sudo docker start -a 155f4b0764b1
root@155f4b0764b1:/# 
=================>
After exit, I have tried ps command:
=====================>
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         21 minutes ago      Up 3 minutes                            zen_volhard
vskumar@ubuntu:~$ 
======================>
From the above display you can see that its start and current status.
It means the container is active and running.
Now, I want to make another [below] container active.
1dd55efde43f        hello-world         "/hello"                13 hours ago Exited (0) 13 hours ago                        peaceful_pasteur
Let us see the ps command after these 2 containers are in active state.
I want to use the below command:
$ sudo docker start -a 1dd55efde43f
===================>
vskumar@ubuntu:~$ sudo docker start -a 1dd55efde43f

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
 1. The Docker client contacted the Docker daemon.
 2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
    (amd64)
 3. The Docker daemon created a new container from that image which runs the
    executable that produces the output you are currently reading.
 4. The Docker daemon streamed that output to the Docker client, which sent it
    to your terminal.

Let us  try something more ambitious, we can run an Ubuntu container with:
 $ docker run -it ubuntu bash

If you want to;
Share images, automate workflows, and more with a free Docker ID:
visit: https://cloud.docker.com/
For more examples and ideas, visit:
https://docs.docker.com/engine/userguide/

vskumar@ubuntu:~$ 
===================>
Please note the above container doesn't have a any os related process to 
keep running continuously. 
Just it displays the message only. Hence 
in the list it will not appear. 
Now, let me list the current processes using docker ps command:
===========>
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         32 minutes ago      Up 14 minutes                           zen_volhard
vskumar@ubuntu:~$ 
==============>
So as on now one container is running.

The next set of container controlling subcommands are docker pause and docker unpause.

The docker pause subcommand will freeze the execution of all the processes within the container.

The docker unpause subcommand will unfreeze the execution of all the processes within the container and resume the execution from the point where it was frozen.

Let us try the below command 
$sudo docker pause 155f4b0764b1
========================>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker pause 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                   PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         About an hour ago   Up 30 minutes (Paused)                       zen_volhard
vskumar@ubuntu:~$ 
==========================>
You can see the current status as Paused.
Now let me try unpause command also.
$ sudo docker unpause 155f4b0764b1
You can see the total output of this container with pause and unpause statuses:
===================>
vskumar@ubuntu:~$ 
vskumar@ubuntu:~$ sudo docker pause 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                   PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         About an hour ago   Up 30 minutes (Paused)                       zen_volhard
vskumar@ubuntu:~$ ^C
vskumar@ubuntu:~$ sudo docker unpause 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
155f4b0764b1        ubuntu:16.04        "/bin/bash"         About an hour ago   Up 32 minutes                           zen_volhard
vskumar@ubuntu:~$ 
======================>
Now, in this lab session finally we will use the stop command:

The container and the script running within it can be stopped using the docker stop subcommand, as shown below:

$ sudo docker stop 155f4b0764b1
=====================> 
vskumar@ubuntu:~$ sudo docker stop 155f4b0764b1
155f4b0764b1
vskumar@ubuntu:~$ sudo docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED STATUS              PORTS               NAMES
=============== It shows there is no active container =============>
Now, let me try with -a and more options.
=========== Partial display is shown here upto the container ===========>
vskumar@ubuntu:~$ sudo docker ps -a |more
CONTAINER ID        IMAGE               COMMAND                 CREATED         
    STATUS                         PORTS               NAMES
f123dbd09116        ubuntu:16.04        "/bin/bash"             6 minutes ago   
    Exited (0) 5 minutes ago                           elastic_nightingale
3cfdea29ce6e        ubuntu              "bash"                  14 minutes ago  
    Exited (0) 14 minutes ago                          gallant_nobel
155f4b0764b1        ubuntu:16.04        "/bin/bash"             About an hour ag
o   Exited (0) 17 seconds ago  
================================>

So far in this lab session, we have seen the differences of different commands to operate and control the containers. I would like to break this session for now. In the next blog we will see on how to manage “Housekeeping containers“.

 Vcard-Shanthi Kumar V