Jenkins is the leading open-source automation server for CI/CD pipelines. This guide installs the latest LTS Jenkins on Ubuntu 24.04 LTS with Java 21 and configures it behind Nginx.

Tested and valid on:

Ubuntu 24.04 LTS

Prerequisites

Ubuntu 24.04 LTS server
Minimum 1 GB RAM (2 GB recommended)
A user with sudo privileges

Step 1 – Install Java 21

Jenkins requires Java 11 or later. Install OpenJDK 21:

sudo apt update
sudo apt install openjdk-21-jdk -y
java -version

Step 2 – Add the Jenkins Repository

Import the Jenkins GPG key and add the repo:

sudo wget -O /usr/share/keyrings/jenkins-keyring.asc https://pkg.jenkins.io/debian-stable/jenkins.io-2023.key
echo "deb [signed-by=/usr/share/keyrings/jenkins-keyring.asc] https://pkg.jenkins.io/debian-stable binary/" | sudo tee /etc/apt/sources.list.d/jenkins.list

Step 3 – Install Jenkins

Install from the official repo:

sudo apt update
sudo apt install jenkins -y

Step 4 – Start and Enable Jenkins

Start Jenkins and enable on boot:

sudo systemctl start jenkins
sudo systemctl enable jenkins

Step 5 – Open the Firewall

Allow Jenkins on port 8080:

sudo ufw allow 8080
sudo ufw allow OpenSSH
sudo ufw enable

Step 6 – Unlock Jenkins

Get the initial admin password:

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

Visit http://your_server_ip:8080, enter the password, and complete the setup wizard.

Step 7 – Configure Nginx Reverse Proxy

Create an Nginx proxy for Jenkins:

sudo nano /etc/nginx/sites-available/jenkins

Add:

server {
    listen 80;
    server_name jenkins.example.com;
    location / {
        proxy_pass http://localhost:8080;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    }
}

Enable and reload:

sudo ln -s /etc/nginx/sites-available/jenkins /etc/nginx/sites-enabled/
sudo nginx -t && sudo systemctl reload nginx

Conclusion

Jenkins is now running on Ubuntu 24.04 LTS. Install the recommended plugins and create your first pipeline to automate builds, tests, and deployments.

How to Install Jenkins on Ubuntu 24.04