What is Jenkins? Jenkins is a free and open source automation tool that can be used to automate repetitive technical tasks with the help of continuous integration and continuous delivery.

In this tutorial, we will explain how to install Jenkins with Docker on Ubuntu 18.04 server. We will also explain how to run Jenkins with Docker in a way to keep Jenkins data and configurations persistent.

Requirements

• A server running Ubuntu 18.04 with minimum 2 GB of RAM.
• A root password is set up on your server.

Getting Started

Let’s start to update your server’s repository with the latest version. You can update it with the following command:

Once the repository has been updated, restart your server to apply all these changes.

Install Docker

Next, you will need to install Docker in your server.

First, download and add Docker CE GPG key with the following command:

Next, add the Docker CE repository to APT with the following command:

Add the following line:

Save and close the file, when you are finished. Then, update the repository with the following command:

Once the repository is updated, install Docker CE with the following command:

After installing Docker CE, verify the Docker installation with the following command:

Create Docker Volume for Data and Log

Docker volume is a method for persisting data and configuration in Docker containers. When you remove any container, the data and configurations are still available in the Docker volume. So you will need to create a data and log volumes to backup Jenkins data and configurations including, logs, plugins, plugin configuration and job config.

Let’s start with creating volume for data and log with the following command:

Once the volumes are created, you can list them with the following command:

You should see the following output:

Install Jenkins with Docker

Next, you will need to create a docker file to pull and build Jenkins image with required settings.

You can create docker file with the following command:

Add the following lines:

Save and close the file, when you are finished. Then, build the Jenkins image with the following command:

You should see the following output:

The new Jenkins image with name myjenkins has been built successfully.

Run Jenkins Container with Data and Log Volume

Jenkins image is now built with required settings. Next, you will need to run Jenkins container by specifying data and log volumes as a mount point.

You can run the Jenkins container with the following command:

Once the Jenkins container is started, you can verify the running container with the following command:

You should see the following output:

Next, you will need to check the jenkins log file whether everything is working fine or not:

You should see the following output:

Please use the following password to proceed to installation:

Please note the above password, you will need it during the Jenkins web set up wizard.

Access Jenkins Web Interface

Now, open your web browser and type the URL http://your-server-ip:8080. You will be redirected to the Jenkins setup screen as shown below:

Provide your administrator password and click on the Continue button. You should see the following page:

Now, click on the “Install suggested plugins” to install the required plugins. Once the installation has been finished. You should see the following page:

Now, provide your admin username, password and full name then click on the Save and Finish button. You should see the following page:

Now, just click on the Save and Finish button. Once the setup completed successfully, you should see the following page:

Now, click on the “Start using Jenkins“. You will be redirected to the Jenkins dashboard as shown in the following page:

Now, click on the “create new jobs” button. You should see the following page:

Now, provide your job name and click on the OK button. You should see the following page:

Now, click on the Save button to save all the settings. You should see your newly created jobs in the following page:

Test Jenkins Persistent Data

Jenkins is now installed and configured. Next, you will need to test whether Jenkins data and log are still persisting after removing the Jenkins container.

To do so, first stop and delete the Jenkins container with the following command:

Now, start the Jenkins container again with the following command:

Once the Jenkins container has been started, open your web browser and type the URL http://your-server-ip:8080. You will be redirected to the following page:

Now, provide your admin user name and password then click on the Sign in button. You should see the Jenkins dashboard in the following page:

That means you have preserved all the data, logs, setup configuration and plugin installs. You should also see that your myjenkinsjob is still there.

CONCLUSION

Now you can containerize your devop process with Jenkins and Docker, enjoy.