Jenkins Docker image

Custom Jenkins image based on jenkins/jenkins:lts-jdk21 (latest LTS, JDK 21).

What's inside

• Base image: jenkins/jenkins:lts-jdk21 (latest LTS)
• Setup wizard disabled (-Djenkins.install.runSetupWizard=false)
• Plugins preinstalled from plugins.txt
• Init scripts in init.groovy.d/ (0 executors on the built-in node, workspace cleanup thread disabled)

Build

docker build -t bndynet/jenkins .

Or use the helper script:

./rebuild.sh # build & run, plugins downloaded at build time ./rebuild.sh --predownloaded # slow networks: pre-download plugins first

On slow networks, --predownloaded runs sync-plugins.py first, which downloads all plugins and their dependencies from a China-friendly mirror into plugins/, so the build itself needs no network access for plugins.

Start a container

All Jenkins data lives in /var/jenkins_home (plugins, jobs, configuration). Make it a persistent volume (recommended):

docker run --name my-jenkins \
  -p 8080:8080 -p 50000:50000 \
  -v jenkins_home:/var/jenkins_home \
  -d \
  bndynet/jenkins

To let Jenkins build Docker images (docker-in-jenkins), also mount the Docker socket:

docker run --name my-jenkins \
  -p 8080:8080 -p 50000:50000 \
  -v jenkins_home:/var/jenkins_home \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -d \
  bndynet/jenkins

The container runs as the jenkins user. To grant access to /var/run/docker.sock, add the jenkins user (uid 1000) to the host's docker group instead of running the container with --user root.

Run bash

docker exec -it my-jenkins bash

Notes

• Setup wizard is disabled, so there is no initial admin password — /var/jenkins_home/secrets/initialAdminPassword is not generated.
• Security is not configured out of the box (anonymous full access). Configure it with the already-installed configuration-as-code (JCasC) and/or matrix-auth plugins.

Reset a forgotten password

If you have enabled security and locked yourself out:

1. Stop Jenkins: docker stop my-jenkins
2. Open config.xml in the Jenkins home volume
3. Find <useSecurity>true</useSecurity> and change it to <useSecurity>false</useSecurity>
4. Start Jenkins: docker start my-jenkins