Variable Name	Description	Default Value
JENKINS_VERSION	Jenkins image version	`2.486-lts-jdk17`
JENKINS_HTTP_PORT_OVERRIDE	Host port mapping for HTTP (maps to port 8080)	8080
JENKINS_AGENT_PORT_OVERRIDE	Host port mapping for agents (maps to port 50000)	50000
JENKINS_OPTS	Additional Jenkins options	`--httpPort=8080`
JAVA_OPTS	Java JVM options	`-Djenkins.install.runSetupWizard=false -Xmx2g`
CASC_JENKINS_CONFIG	Configuration as Code directory	`/var/jenkins_home/casc_configs`
JENKINS_USER_ID	User ID for Jenkins process	1000
JENKINS_GROUP_ID	Group ID for Jenkins process	1000

Please modify the .env file as needed for your use case.

Volumes

jenkins_home: A volume for storing Jenkins data, configuration, and workspace.
/var/run/docker.sock: Docker socket (read-only) for Docker-in-Docker functionality.
./jenkins.yaml: Optional Configuration as Code file.

Initial Setup

Start the service:
```
docker compose up -d
```

Get the initial admin password:

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

Access Jenkins at http://localhost:8080 and complete the setup wizard.

Configuration as Code

Jenkins can be configured using Configuration as Code (JCasC). Create a jenkins.yaml file with your configuration and mount it to /var/jenkins_home/casc_configs/jenkins.yaml.

Example configuration:

jenkins:
  systemMessage: "Jenkins configured automatically by Jenkins Configuration as Code plugin"
  
  securityRealm:
    local:
      allowsSignup: false
      users:
       - id: admin
         password: admin123

  authorizationStrategy:
    loggedInUsersCanDoAnything:
      allowAnonymousRead: false

Security Notes

Change the default admin password immediately after setup
Consider using HTTPS for production deployments
Regularly update Jenkins and its plugins for security patches
Use proper authentication and authorization strategies
Restrict access to the Jenkins web interface