How to Install Jenkins Using Docker

Jenkins is a popular open-source automation server that helps streamline the CI/CD process. In this guide, we will cover the steps to install Jenkins using Docker.

Prerequisites

• Docker installed on your machine. If not, follow the Docker installation guide.
• Basic understanding of Docker commands.
• Internet connectivity to pull the Jenkins Docker image.

Steps to Install Jenkins

Step 1: Pull the Jenkins Docker Image

Use the following command to pull the Jenkins LTS (Long Term Support) image from Docker Hub:

docker pull jenkins/jenkins:lts

Step 2: Create a Docker Volume for Jenkins Data

Create a volume to persist Jenkins data across container restarts:

docker volume create jenkins_data

Step 3: Run the Jenkins Container

Start a Jenkins container with the following command:

docker run -d \  
  -p 8080:8080 \  
  -p 50000:50000 \  
  --name jenkins \  
  -v jenkins_data:/var/jenkins_home \  
  jenkins/jenkins:lts

Explanation of the options:

• -d: Runs the container in detached mode.
• -p 8080:8080: Maps port 8080 on your host to port 8080 in the container (Jenkins UI).
• -p 50000:50000: Maps port 50000 for Jenkins agents.
• -v jenkins_data:/var/jenkins_home: Mounts the jenkins_data volume to persist Jenkins configuration and job data.

Step 4: Access Jenkins

Once the container is running, open your browser and navigate to http://localhost:8080.

On the first launch, Jenkins will prompt for an administrator password. Retrieve it using the command:

docker exec jenkins cat /var/jenkins_home/secrets/initialAdminPassword

Copy the password and paste it into the setup wizard to continue with the initial configuration.

Step 5: Complete Initial Setup

Follow the on-screen instructions to:

• Install recommended plugins.
• Create an admin user account.
• Configure Jenkins as needed.

Conclusion

Congratulations! You have successfully installed Jenkins using Docker. You can now start creating jobs and setting up your CI/CD pipelines.