How To Install Jenkins on Ubuntu 22.04 | DigitalOcean

Introduction

Jenkins is an open source automation server that automates the repetitive technical tasks involved in continuous software integration and delivery. Jenkins is Java-based, installed from Ubuntu packages or by downloading and running its Web Application Archive (WAR) file, a collection of files that make up a complete web application to run on a server.

In this tutorial, you will install Jenkins on Ubuntu 22.04, start the development server, and create an administrative user to start exploring Jenkins automation. By the end of this tutorial, you will have an unsecured Jenkins server ready for a development deployment. To secure your installation for production, follow the guide How to configure Jenkins with SSL using an Nginx reverse proxy in Ubuntu 22.04.

Prerequisites

To follow this tutorial, you will need:

An Ubuntu 22.04 server

• configured with a non-root sudo user and firewall following the Ubuntu 22.04 starter server setup guide. We recommend starting with at least 1 GB of RAM. Visit Jenkins’ “Hardware Recommendations” for guidance on capacity planning for a production-level Jenkins installation.
• Oracle JDK 11 installed, following our guidelines on installing specific versions of OpenJDK on Ubuntu 22.04.

Step 1 — Installing

Jenkins The version of

Jenkins included with Ubuntu’s default packages is often behind the latest available version of the project itself. To ensure that you have the latest fixes and features, use the packages maintained by the project to install Jenkins.

First, add the repository key to

your system

: wget -q -O – https://pkg.jenkins.io/debian-stable/jenkins.io.key |sudo gpg -dearmor -o /

1. usr/share/keyrings/jenkins.gpg The gpg -dearmor command

is used to convert the key into a format that apt recognizes

.

Next, let’s add the repository address of the Debian package to

sources.list on the server: sudo sh -c ‘echo deb [ signed-by=/usr/share/keyrings/jenkins.gpg] http://pkg.jenkins.io/debian-stable binary/ > /etc/apt/sources.list.d/jenkins.list

1. ‘ The [signed-by

=/

usr/share/keyrings/jenkins.gpg] part of the line guarantees that apt will verify the files in the repository using the GPG key you just downloaded.

After entering both commands, run apt update so that apt uses the new repository.

1. sudo apt update

Finally

, install Jenkins and its dependencies: sudo apt install jenkins Now that Jenkins

and its dependencies are in place, we’ll start the

Jenkins server.

Step 2 — Starting

Jenkins Now that Jenkins is

installed, start it using

systemctl: sudo systemctl start

1. jenkins.service

Since systemctl does not show the status output,

we will use the status command to verify that Jenkins started successfully:

1. sudo systemctl status

jenkins

If all went well, the beginning of the state output shows that the service is active and configured to start at boot

: Output● jenkins.service – Jenkins Continuous Integration Server Loaded: loaded (/lib/systemd/system/jenkins.service; enabled; provider preset: enabled) Active: active (running) since Mon 2022-04-18 16:07:28 UTC; 2min 3s ago Main PID: 88180 (java) Tasks: 42 (limit: 4665) Memory: 1.1G CPU: 46.997s CGroup: /system.slice/jenkins.service └─88180 /usr/bin/java -Djava.awt.headless=true -jar /usr/share/java/jenkins.war -webroot=/var/cache/jenkins/war -httpPort=8080

Now that Jenkins is up and running, adjust your firewall rules so you can access it from a web browser to complete the initial setup.

Step 3 — Open the firewall

To set up a UFW firewall, visit Initial Server Setup with Ubuntu 22.04, Step 4- Setting Up a Basic Firewall. By default, Jenkins runs on port 8080. Open that port using

ufw: sudo ufw allow 8080 Check the ufw status

to confirm the new rules

:

1. sudo ufw status

You will notice that traffic can carry

8080 from anywhere: OutputStatus: active For action from – – – OpenSSH ALLOW Anywhere 8080 ALLOW Anywhere OpenSSH (v6) ALLOW Anywhere (v6)

1. 8080

(v6) ALLOW Anywhere (v6)

With Jenkins installed and a firewall configured, you have completed the installation stage and can proceed with the Jenkins setup.

Step 4 — Jenkins Setup

To configure your installation, visit Jenkins on its default port, 8080,

using your server’s domain name or IP address: http://your_server_ip_or_domain:8080

You should receive the Unlock Jenkins screen

, which shows the location of the initial password:

In the terminal window, use the cat command to display

the password:

1. sudo cat /var/lib/jenkins/secrets/initialAdminPassword

Copy the 32-character alphanumeric password from the terminal and paste it into the Administrator password field, then click Continue.

The following screen presents the option to install suggested plugins or select specific plugins:

<img

src=”https://assets.digitalocean.com/articles/jenkins-install-ubuntu-1804/customize_jenkins_screen_two.png” alt=”Customize Jenkins screen” />

We will click on the Install suggested plugins option, which will immediately start the installation process.

When the installation is complete, you are prompted to configure the first administrative user. It is possible to skip this step and continue as administrator using the initial password above, but we will take a moment to create the user.

Enter the user’s name and password:

You will receive an instance configuration which will prompt you to confirm the preferred URL for your Jenkins instance. Confirm the server domain name or server IP address:

After confirming the appropriate information, click Save and Finish. You will receive a confirmation page confirming that

“Jenkins is ready”: <img src="https://assets.digitalocean.com/articles/jenkins-install-ubuntu-1804/jenkins_ready_page_two.png" alt="Jenkins

is ready screen” />

Click Start using Jenkins to visit the main Jenkins dashboard:

At this

point, you have completed a successful installation of

Jenkins.

Conclusion

In this tutorial, you installed Jenkins using the packages provided by the project, started the server, opened the firewall, and created an administrative user. At this point, you can start exploring Jenkins.

When you have completed your scan, follow the guide How to configure Jenkins with SSL using an Nginx reverse proxy in Ubuntu 22.04 to protect your passwords as well as any sensitive system or product information that will be sent between your machine and the server in plain text to continue using Jenkins.

For more information on what you can do using Jenkins, check out other tutorials on the topic:

How to

• Build Android Apps with

Jenkins

• How to Set Up Continuous Integration Pipelines in Jenkins on Ubuntu 16.04