Overview

Now we can quickly provision a Jenkins instance in a container, next it would be useful to be able to automate all subsequent deployment. Including:

  • Management configuration (users, groups, directory integration)
  • Plugin deployment
  • Plugin configuration

Jenkins Configuration as Code (aka JCasC) can help with these post-deployment steps.

How-to

  1. If Jenkins is already up and running, skip to step #2.

    If starting from scratch, podman run the Jenkins LTS release

     $ podman run -d --restart on-failure -p 8080:8080 -u $UID -v jenkins_home:/var/jenkins_home --name jenkins docker.io/jenkins/jenkins:lts

    If you already have a Jenkins container and volume, but it’s shutdown, start it back up:

     $ podman start jenkins

  2. Install the Jenkins Configuration as Code plugin:

     $ podman exec -it jenkins jenkins-plugin-cli --plugins configuration-as-code:1958.vddc0d369b_e16
 Done

  3. Validate the installed plugins:

     $ podman exec -it jenkins jenkins-plugin-cli --list
 Installed plugins:
 antisamy-markup-formatter 173.v680e3a_b_69ff3
 asm-api 9.8-135.vb_2239d08ee90
 bootstrap5-api 5.3.3-2
 caffeine-api 3.2.0-166.v72a_6d74b_870f
 commons-lang3-api 3.17.0-87.v5cf526e63b_8b_
 commons-text-api 1.13.0-153.v91dcd89e2a_22
 configuration-as-code 1958.vddc0d369b_e16
 font-awesome-api 6.7.2-1
 json-api 20250107-125.v28b_a_ffa_eb_f01
 plugin-util-api 6.1.0
 prism-api 1.30.0-1
 scm-api 704.v3ce5c542825a_
 script-security 1373.vb_b_4a_a_c26fa_00
 snakeyaml-api 2.3-125.v4d77857a_b_402
 structs 343.vdcf37b_a_c81d5
 workflow-api 1371.ve334280b_d611
 workflow-step-api 700.v6e45cb_a_5a_a_21
 workflow-support 968.v8f17397e87b_8
 <...>

    Note: In the UI these plugins will not be shown as installed. A restart is required.

  4. Restart Jenkins:

     $ podman stop jenkins && podman start jenkins

    Note: A straight podman restart jenkins fails to bind to the port. Possibly a pasta issue.

Notes

Quick clean up

If you need to start from scratch you can quickly reset by:

$ podman stop jenkins
$ podman rm jenkins
$ podman volume rm jenkins_home

Safe restart

We can call safe-restart using Jenkins CLI option, but we still need to start the container from the container host, even if --restart always is set.

$ podman exec -it jenkins sh -c 'java -jar /var/jenkins_home/war/WEB-INF/lib/cli-2.492.3.jar -s http://localhost:8080 -auth admin:`cat /var/jenkins_home/secrets/initialAdminPassword` safe-restart'

Note #2: From outside the pod, we need to use sh -c to permit the backticks/subshell to be passed to the pod unmolested. Inside the pod we can just run java -jar /var/jenkins_home/war/WEB-INF/lib/cli-2.492.3.jar -s http://localhost:8080 -auth admin:cat /var/jenkins_home/secrets/initialAdminPassword safe-restart

Next Steps

Now we can do Configuration as Code for Jenkins.

Tack on an AD instance, set up groups automatically.

References