Lab 25:Jenkins setup

                                                             Jenkins setup

Continuous integration is the most important part of develops that is used to integrate various devops stages.Jenkins is the most famous and continuous integration tool.

 Jenkins s an open automation tool written in java with plugins built for continuous integration purpose. Jenkins is used to build and test  your software projects continuously making it easier for developers to integrate to the project changes to the project and making it , and making it easier for users to obtain a fresh build . It also allows you to continuously deliver you software by integrating with a large number of testing and deployment technologies

Pre-Requirements:

Create an instance

Install java,Jenkins ,docker ,git ,in an instance

Sign in git hub,create a repository

Create a httpd   image in your local repo

First create a repo in central repository

If you don’t have an account refer the below link and create an account

https://github.com/

From the above link create an account

After creating an account In the git hub create a respository

àrepo is nothing but software storing locations

You will get a page like this

Give a name for the project

And a description

 

And then click on create

You will get page like this

 

Now create local repo

Create a simple docker file push to get hub

Open git bash

 

Now copy the created repo url

 

Use the command git clone<url>

•         Git clone command copies an existing git repository in a directory at another location.

 

You have created a repo in your local system

Now create a simple httpd file

Go inside the created repository

Cd Jenkins_ci

In that create a httpd fileàvi docker file -àwrite the below lines in vi docker file

FROM httpd

COPY index.html/usr/local/apache2/htdocs/

To insert the vi editor press esc and enter i and enter above lines

After entering save and exit

 

Esc shift+: and write wq! To save the content and exit

We just created a file its untracked file

To track the file and add the file

Use the command git add<filename>

 

To see the status of a file enter the command git status

Now file is tracked but still is temporary we want to do permanent we need to commit the file

#git commit-m <message>  

 

Now create an index file

 #vi index .html

And write any one like Jenkins

 

Save and come out of the editor

Now index.html is untracked file.

To track the file add the file

Git add <filename>

 

Now the file is tracked but its in temporary and to do permanent commit the file

#git commit –m<message>

                                                           

Check the status

git status

Now push this files get hub

Before that set the environmental variables

git-config—global user .email  mailid --------give the email

gitconfig  --global user.name    username-------give the user name

Note :Give the same mail id which you have used for the account  in git hub and same user name for git hub.

 

No login to remote repository which means git hub

Use the below command

#git remote add orign git@github.com:<username>/jenkins  ci.git

If you already login it will stay remote orign already exists.

Next push the files to remote repo

Now check the github whether the files came or not

 

Files are there

We will use this repo url while creating a job in Jenkins

Step2:create an instance

Refer above how to create an ec2 instance

Select redhat ami.

Give security groups ssh and all tcp

Login to the server ssh and use public ip address of an instance

 

Without java Jenkins won’t work so before installing Jenkins install java.

#yum install java-1.8.0-openjdk-devel

To check the version of java use command java-version

 

Now install the Jenkins

Before that enable the epel

#  curl  --silent  --location  http://pkg.jenkins-ci.org/redhat-stable/jenkins.repo| sudo  tee /etc/yum.respos.d/Jenkins.repo

Now install the Jenkins

#yum install jenkins—nogpgcheck—y

 

Start and enable the Jenkins

Systemctl start Jenkins

Systemctl enable Jenkins

 

Enable the Jenkins to os level

 

Now check whether the Jenkins running or not.

#ps-ef | grep-i jenkins

 

You get a single line status means Jenkins is not working

Now install docker and git as well

#yum install docker and start the service

#systemctl start docker

Before that enable the epel

Then install docker and start service

 

Now start the service

systemctl start docker

systemctl enable docker

 

Now check the docker is running or not

#ps-ef|grep -i docker

Now install git

#yum install git

 

Now lets connect to the Jenkins

Open in the browser by using public <ipaddress>:8080

Because Jenkins will run on 8080 port number

Now copy url and paste in the server to get password to login to Jenkins .

#cat/var/lib/Jenkins/secrets/initialAdminpassword

 

Copy that password and paste in Jenkins url

Click on continue

You will get a page like this

Select install suggested plugins.

  

You will get a page like this

 

Just provide all the details

After providing details just click on save and continue

You will get a page like this

Click on save and finish

 

Click on start using Jenkins

You will get a page like this

 

Create a job 

click on create new job or else click on create new item

Item is nothing but a job

Enter an item name

 

Select the job style

Select free style project

Then click on ok

You will get a page like this

 

Give a description

 

And then click on source code management select git

Here give the repo url which we created in the git hub

 

Give this url

 

Now come to build section

Drop down build setup

Select execute shell

From here we build the image

 

You will get a page like this here we can run commands

echo "i am bulding docker image"

Sudo docker build -t httpd-web:1.

Echo "list the docker images"

Sudo docker images

echo "login to the docker hub"

Sudo docker login -u xxxx -p xxxxxx

Echo "tag the local image"

Sudo docker tag httpd -web:1<username>/httpd-web:$image tag

Echo "push the image into docker hub"

Sudo docker push<username>/httpd-web:1

 

Click on apply and save

 

Click build now to build the image

Build has failed

Click on 1 to see the console out put to see why the build has failed

 

Click on console output

While install Jenkins it will create an use called Jenkins user as jenkin is normal user he cant built the image

Make Jenkins as sudoer user go to the bit bash

Enter visudo

vieditor will open make jenkin as sudoer where he can have all the right to do

Go to the 93 line enter jenkin   ALL=(ALL) Nopasswd :all

 

Save and Quit

Now come to the Jenkins UI and build the image again

 

Build failed

Go to console output see the error

 

Image is built but cannot push to the docker hub

As we took redhat ami we cannot to the docker hub

We need to edit the /etc/container/registries.d file

Go to the bit bash vi/etc/containers /registries.conf

Set the line numbers  edit the line number 12 just keep docker .io in double quotes remaining delete

 

Save and quit

And restart the service

#systemctl restart docker

 

Come to the Jenkins page and again build the image

Now image got build

 

Now go to docker hub and check whether the image pushed or not

Execrise :1)Install the Jenkins in redhat and ubuntu ami.

2)Make Jenkins user’s as a sudoer user.