Install Jenkins using docker

1. Open up a terminal window.

2. Firstly, Create a directory new name terminal

    mkdir  Jenkins
   

3. Change the directory / Jenkins

    cd  Jenkins
   

4. Create another DockerFile and write nano Dockerfile in a terminal

    sudo nano Dockerfile
   

5. Build and Run

sudo docker build -t jenkins:lastest
sudo docker run -p 8080 -d -v var/jenkins_home/docker:var/jenkins_home/docker

# GNU nano 4.8 Dockerfile 
FROM jenkins/jenkins:lts

#Switch to the root user to install additional packages

USER root

# Install prerequisites and Docker

RUN apt-get update && apt-get install -y apt-transport-https ca-certificates curl software-properties-common 
RUN curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add - 
RUN add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/debian $(lsb_release -cs) stable" 
RUN apt-get update && apt-get install -y docker-ce

# Switch back to the Jenkins user

USER jenkins

# Expose Jenkins web interface on port 8080

EXPOSE 8080 

# Start Jenkins

CMD ["/usr/local/bin/jenkins.sh"]

 sudo docker ps -a

DESKTOP-TQ2GRMA:~$ sudo docker exec -it 7c7 bash
Sudo password for jenkins

Accessing the Jenkins home directory

You can access the Jenkins home directory, to check the details of a Jenkins build in the workspace subdirectory, for example.

If you mapped the Jenkins home directory (/var/jenkins_home) to one on your machine’s local file system, for example, in the docker run …​ command above, access the directory contents through your machine’s usual terminal/command prompt.

If you specified the --volume jenkins-data:/var/jenkins_home option in the docker run …​ command, access the contents of the Jenkins home directory through your container’s terminal/command prompt using the docker container exec command:

docker container exec -it <docker-container-name> bash

As per the previous section, get your <docker-container-name> using the docker container ls command. If you specified the --name jenkins-blueocean option in the docker container run …​ the command above (refer to Accessing the Jenkins/Blue Ocean Docker container if needed), use the docker container exec command:

docker container exec -it Dockerfile bash

Post-installation setup wizard

After downloading, installing and running Jenkins using one of the procedures above (except for installation with Jenkins Operator), the post-installation setup wizard begins.

This setup wizard takes you through a few quick "one-off" steps to unlock Jenkins, customize it with plugins and create the first administrator user through which you can continue accessing Jenkins.

Unlocking Jenkins

When you first access a new Jenkins instance, you are asked to unlock it using an automatically-generated password.

1. Browse to http://localhost:8080 (or whichever port you configured for Jenkins when installing it) and wait until the Unlock Jenkins page appears.

   

2. From the Jenkins console log output, copy the automatically-generated alphanumeric password (between the 2 sets of asterisks).

   Note:

   • The command: sudo cat /var/lib/jenkins/secrets/initialAdminPassword will print the password at the console.

   • If you are running Jenkins in Docker using the official jenkins/jenkins image you can use sudo docker exec ${CONTAINER_ID or CONTAINER_NAME} cat /var/jenkins_home/secrets/initialAdminPassword it to print the password in the console without having to exec into the container.

       sudo cat /var/lib/jenkins/secrets/initialAdminPassword
       # cat /var/jenkins_home/secrets/initialAdminPassword
       $ unlock your password for jenkins first level
     

3. On the Unlock Jenkins page, paste this password into the Administrator password field and click Continue.
   Note:

   • The Jenkins console log indicates the location (in the Jenkins home directory) where this password can also be obtained. This password must be entered in the setup wizard on new Jenkins installations before you can access Jenkins’s main UI. This password also serves as the default administrator account’s password (with username "admin") if you happen to skip the subsequent user-creation step in the setup wizard.

     Then after login and password you will enter jenkins dashboard.

     

     Just Click Configure and General despcrition

     

     Soure code management

     • Click Git and Repositories?

       Downward Repository URL : give url of github

       Build Environment

         export BUILD_NO=$BUILD_NUMBER
         echo "password" | sudo -S docker build -t sitename:$BUILD_NO .
       

Customizing Jenkins with plugins

After unlocking Jenkins, the Customize Jenkins page appears. Here you can install any number of useful plugins as part of your initial setup.

Click one of the two options shown:

• Install suggested plugins - to Install the recommended set of plugins, which are based on the most common use cases.

• Select plugins to install - to choose which set of plugins to initially install. When you first access the plugin selection page, the suggested plugins are selected by default.

The setup wizard shows the progression of Jenkins being configured and your chosen set of Jenkins plugins being installed. This process may take a few minutes.

Creating the first administrator user

Finally, after customizing Jenkins with plugins, Jenkins asks you to create your first administrator user.

1. When the Create First Admin User page appears, specify the details for your administrator user in the respective fields and click Save and Finish.

2. When the Jenkins is ready page appears, click Start using Jenkins.
   Notes:

   • This page may indicate Jenkins is almost ready! instead and if so, click Restart.

   • If the page does not automatically refresh after a minute, use your web browser to refresh the page manually.

3. If required, log in to Jenkins with the credentials of the user you just created and you are ready to start using Jenkins!