How to set up and start Jenkins using Docker?

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Accepted Answer

Running Jenkins in a Docker container is the quickest way to get started, as it eliminates manual dependency installations and provides isolation. The official Jenkins image includes everything needed to run Jenkins, and you can customize it by mounting volumes for persistent storage and accessing the Docker daemon from within the container . # Pull the latest Jenkins LTS image
docker pull jenkins/jenkins:lts

# Run Jenkins container with port mappings and persistent volume
docker run -d \
  -p 8080:8080 \
  -p 50000:50000 \
  --name jenkins \
  -v jenkins_home:/var/jenkins_home \
  jenkins/jenkins:lts

# Explanation:
# -d           : Run container in detached mode (background)
# -p 8080:8080 : Map host port 8080 to container port 8080 (web UI)
# -p 50000:50000: Map agent communication port
# --name jenkins: Assign a friendly name to the container
# -v jenkins_home:/var/jenkins_home: Persist Jenkins data in a Docker volume  For Jenkins to build and run Docker containers as part of your CI/CD pipelines, it needs access to the Docker daemon. The cleanest approach is to mount the host's Docker socket into the Jenkins container. This gives Jenkins the ability to execute Docker commands without running Docker-in-Docker . # Stop and remove the previous container if running
docker stop jenkins && docker rm jenkins

# Run with Docker socket mounted
 docker run -d \
   -p 8080:8080 \
   -p 50000:50000 \
   --name jenkins \
   -v jenkins_home:/var/jenkins_home \
   -v /var/run/docker.sock:/var/run/docker.sock \
   -v $(which docker):/usr/bin/docker \
   jenkins/jenkins:lts

# -v /var/run/docker.sock: Allows Jenkins to communicate with host Docker daemon
# -v $(which docker):/usr/bin/docker: Makes docker CLI available inside container  After starting the container, Jenkins generates an initial admin password. You'll need this to unlock Jenkins during first-time setup. Once unlocked, you can install recommended plugins and create your admin user . # View the initial admin password
docker exec jenkins cat /var/jenkins_home/secrets/initialAdminPassword

# Access Jenkins web UI at http://localhost:8080
# Paste the password, then follow the setup wizard to install plugins and create admin user  Pull the image: `docker pull jenkins/jenkins:lts`  Run with persistence: Use the `-v jenkins_home:/var/jenkins_home` flag to ensure your configurations survive container restarts or upgrades  Map ports: Always map port 8080 for the web UI and optionally port 50000 for agent connections  Add Docker access: Mount the Docker socket (`-v /var/run/docker.sock:/var/run/docker.sock`) to enable Jenkins pipelines to build and run containers  Retrieve the password: Run `docker exec jenkins cat /var/jenkins_home/secrets/initialAdminPassword` to get the initial unlock key  For a more manageable setup, especially when you need to add other services like Nginx or databases, use Docker Compose. Create a `docker-compose.yml` file that defines the Jenkins service with all the necessary volume mounts and port mappings. This is particularly useful for version-controlling your Jenkins configuration and simplifying restarts . version: '3.8'
services:
  jenkins:
    container_name: jenkins
    image: jenkins/jenkins:lts
    restart: always
    ports:
      - "8080:8080"
      - "50000:50000"
    volumes:
      - jenkins_home:/var/jenkins_home
      - /var/run/docker.sock:/var/run/docker.sock
      - /usr/bin/docker:/usr/bin/docker

volumes:
  jenkins_home:

# Start with: docker-compose up -d
# Stop with: docker-compose down  If Jenkins cannot execute Docker commands, verify that the Docker socket is correctly mounted and that permissions are set. For hosts with AppArmor or SELinux restrictions, you may need additional configuration. Also ensure that the Jenkins user inside the container has the necessary permissions—the official image runs as user `jenkins` (UID 1000), and the mounted socket must be readable by that UID .

How to set up and start Jenkins using Docker?

Set up Jenkins using Docker by pulling the official jenkins/jenkins:lts image and running it with the necessary port mappings and volume mounts for persistent data and Docker access

How to set up and start Jenkins using Docker?

Set up Jenkins using Docker by pulling the official jenkins/jenkins:lts image and running it with the necessary port mappings and volume mounts for persistent data and Docker access

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