🧰 Prerequisites#

A system running Ubuntu 20.04 or later
Sudo privileges

🔧 Step 1: Install Java#

Jenkins requires Java to run. We’ll use OpenJDK 21, which is supported by Jenkins.

sudo apt update -y
sudo apt install fontconfig openjdk-21-jre -y
java -version

Expected Output:

openjdk 21.0.6 2025-01-21
OpenJDK Runtime Environment (build 21.0.6+7-Ubuntu-124.04.1)
OpenJDK 64-Bit Server VM (build 21.0.6+7-Ubuntu-124.04.1, mixed mode, sharing)

📦 Step 2: Add Jenkins Repository#

First, import the Jenkins GPG key:

sudo wget -O /usr/share/keyrings/jenkins-keyring.asc \
  https://pkg.jenkins.io/debian-stable/jenkins.io-2023.key

Add the Jenkins repository to your system:

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 > /dev/null

Update your package list:

sudo apt update -y

📥 Step 3: Install Jenkins#

sudo apt-get update -y
sudo apt-get install jenkins -y
sudo systemctl start jenkins
sudo systemctl enable jenkins

🌐 Step 4: Access Jenkins Web UI#

Open a browser and navigate to: http://<your-server-ip>:8080

Retrieve the initial admin password: sudo cat /var/lib/jenkins/secrets/initialAdminPassword

Paste the output of above command into the Jenkins setup wizard to unlock Jenkins.

Conclusion
This is it! You’ve now successfully installed Jenkins with Java! 🎉 From here, you can begin configuring Jenkins, installing plugins, and setting up your first pipelines. Happy automating! If you have any doubts/issues/errors with the above contents, feel free to contact me. Cheers, Happy automating!