Backup Jenkins on Kubernetes

You can use the instructions on this page to create pre and post backup rules with Portworx Backup, which take application-consistent backups for Jenkins on Kubernetes in production.

Jenkins stores data within a directory known as JENKINS_HOME. Workspaces, plug-ins, jobs, user content and overall configuration exist within this directory and are vital when recovering from various types of failures.

See below for a snippet of what this might look like in a Kubernetes spec file.

...
        volumeMounts:
        - name: jenkins-home
          mountPath: /var/jenkins_home
      volumes:
        - name: jenkins-home
          persistentVolumeClaim:
            claimName: jenkins-data
...

Once you configure a PVC to be mounted at /var/jenkins_home you can use the below guide for pre and post backup rules.

Installation

Prerequisites

note

• You should configure a persistent volume for JENKINS_HOME so that the entire directory is backed by a volume to capture all data associated with Jenkins.

• These examples assume that the Jenkins CLI is available within the Jenkins pod. You can make sure it's available in the Jenkins pod(s) by running the below command.

  kubectl exec <jenkins-deployment-pod> -n jenkins -- /bin/sh -c "wget http://<operations-center-url>:>port-number>/jnlpJars/jenkins-cli.jar -O /var/jenkins_home/cli.jar"

Create rules for Jenkins

Create rules for Jenkins that will run both before and after the backup operation runs:

Create a pre-exec backup rule for Jenkins

Assume the Jenkins deployment has a job called job-1, you will use the pre-exec rule to make sure this job is stopped before taking our snapshot.

note

Stopping a job is not necessary to back up Jenkins. It is used as an example of a pre backup rule. You may run other commands available within the Jenkins pod here as well.

1. Navigate to Settings → Rules → Add New.

2. Add a name for your Rule.

3. Add the following app label:

   app=jenkins

4. Add the following action:

   java -jar /var/jenkins_home/cli.jar -s http://jenkins:8080 -webSocket -auth username:password stop-builds job-1

   

Create a post-exec backup rule for Jenkins

After your backup is triggered, you can start the build for job-1 again using a post-exec rule. This ensures your job is not running during the backup and is restarted after the backup data is captured.

1. Navigate to Settings → Rules → Add New.

2. Add a name for your Rule.

3. Add the following app label:

   app=jenkins

4. Add the following action:

   java -jar /var/jenkins_home/cli.jar -s http://jenkins:8080 -webSocket -auth username:password build job-1

   

Use the rules during backup of Jenkins

During the backup creation process, select the rules in the pre-exec and post-exec dropdowns:

Once you have filled out the backup form, click Create

Demo

Watch this short demo of the above information.