Installation of Jenkins in Ubuntu (original) (raw)

Last Updated : 9 Feb, 2026

Jenkins is an open-source automation tool used to implement Continuous Integration and Continuous Delivery (CI/CD) in software projects. It is built in Java and helps automate tasks such as building, testing, and deploying applications.

Written in Java and runs on the Java Virtual Machine (JVM).
Can be installed using system packages or by running the WAR file.
Automates repetitive development and deployment tasks to improve efficiency.

Install Jenkins on Ubuntu: A Step-by-Step Guide

Before installing Jenkins, ensure that the following requirements are met:

An Ubuntu server (22.04)
Root or sudo privileges
1 GB RAM works, but 2 GB RAM is recommended for smooth usage. and 1 CPU core
Jenkins LTS officially supports Java 17 and Java 21

Step 1: Update your system

Before installing any packages, ensure your system is up to date. Open a terminal and run:

sudo apt update
sudo apt upgrade -y

Sudoupdate

Step 2: Install Java

Jenkins requires Java to run. Jenkins LTS officially supports Java 17 and Java 21. Install the OpenJDK 21 package: (Skip this step if Java is already installed).

sudo apt install openjdk-21-jdk -y

file

Verify the Java installation by running:

java -version

**Output:

file

Step 3: Add Jenkins Repository

Import Jenkins key to authenticate the repository:

curl -fsSL https://pkg.origin.jenkins.io/debian-stable/jenkins.io-2026.key | sudo tee /usr/share/keyrings/jenkins-keyring.asc > /dev/null

Add Jenkins repository to your system's package list:

echo "deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] https://pkg.origin.jenkins.io/debian-stable/ binary/" | sudo tee /etc/apt/sources.list.d/jenkins.list > /dev/null

add-the-keys

Step 4: Install Jenkins

Now that Jenkins' repository is added, update the package list again:

sudo apt update

Then install Jenkins:

sudo apt install jenkins -y

installjenkins

Step 5: Start and Enable Jenkins

Once the installation is complete, start the Jenkins service:

sudo systemctl start jenkins

Enable the Jenkins service to start on boot:

sudo systemctl enable jenkins

jenkinsrunning

Step 6: Adjust the Firewall

Jenkins runs on port 8080 by default. If you are using a firewall (e.g., ufw), you'll need to allow traffic on that port.

Allow port 8080 through the firewall:

sudo ufw allow 8080

Reload the firewall to apply changes:

sudo ufw reload

UFW

Step 7: Access Jenkins Web Interface

To access Jenkins, open your web browser and enter your server's IP address or domain name, followed by port 8080:

http://your_server_ip_or_domain:8080

localhost

Step 8: Unlock Jenkins

When you first access Jenkins, it will ask you for an admin password.
Retrieve the password by running this command:

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

Copy the password from the terminal and paste it into the "Administrator password" field in the Jenkins web interface.

Step 9: Install Suggested Plugins

After entering the password, Jenkins will guide you through the initial setup.

Click Install suggested plugins for a default setup.
Wait while Jenkins installs the plugins.

Step 10: Create an Admin User

Once the plugins are installed, Jenkins will prompt you to create your first admin user.

Fill in the required fields (username, password, etc.) to create the admin user.
Click Save and Finish.

Step 11: Start Using Jenkins

After completing the setup, Jenkins will be ready to use. You should see the Jenkins dashboard where you can start creating jobs, configuring builds, and more.