Persistent Volume for Jenkins on Kubernetes

5/4/2020

I'm trying to deploy a Jenkins image on a local Kubernetes cluster. The deployment is succesfull but I can't get the persistence data working. No errors are being thrown and new pods start up succesfully, the only problem is that it's not persistent.

Jenkins Dockerfile:

FROM jenkins/jenkins:lts

ENV JENKINS_USER admin
ENV JENKINS_PASS admin

# Skip initial setup
ENV JAVA_OPTS -Djenkins.install.runSetupWizard=false


COPY plugins.txt /usr/share/jenkins/plugins.txt
RUN /usr/local/bin/install-plugins.sh < /usr/share/jenkins/plugins.txt
USER root
RUN apt-get update \
  && apt-get install -qqy apt-transport-https ca-certificates curl gnupg2 software-properties-common 
RUN curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add -
RUN add-apt-repository \
  "deb [arch=amd64] https://download.docker.com/linux/debian \
  $(lsb_release -cs) \
  stable"
RUN apt-get update  -qq \
  && apt-get install docker-ce -y
RUN usermod -aG docker jenkins
RUN apt-get clean
RUN curl -L "https://github.com/docker/compose/releases/download/1.24.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose && chmod +x /usr/local/bin/docker-compose
USER jenkins

Kubernetes Deployment file:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: jenkins
spec:
  replicas: 1
  selector:
    matchLabels:
      app: jenkins
  template:
    metadata:
      labels:
        app: jenkins
    spec:
      containers:
        - name: jenkins
          image: mikemanders/my-jenkins-image:1.1
          env:
            - name: JAVA_OPTS
              value: -Djenkins.install.runSetupWizard=false
          ports:
            - name: http-port
              containerPort: 8080
            - name: jnlp-port
              containerPort: 50000
          volumeMounts:
            - name: jenkins-home
              mountPath: /var/lib/jenkins
              subPath: jenkins
      volumes:
        - name: jenkins-home
          persistentVolumeClaim:
            claimName: jenkins-pv-claim

Kubernetes persistent volume:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: jenkins-pv
  labels:
    type: local
spec:
  storageClassName: manual
  capacity:
    storage: 6Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: "/var/lib"

Persistent Volume Claim

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: jenkins-pv-claim
spec:
  storageClassName: manual
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 2Gi

I'm using Minikube for local development. And of course Kubectl.

Don't see what i'm doing wrong. All help is appreciated.

-- Mike Manders
docker
jenkins
kubernetes
persistent-volume-claims
persistent-volumes

1 Answer

5/4/2020

The regular dockerhub jenkins image uses the path /var/jenkins_home, not /var/lib/jenkins for persistent data. Therefore you should use that path to mount your persistent volume.

-- Thomas
Source: StackOverflow