Jenkins weekend: Install, Configure for newbies

During the weekend, I wanted to try creating a CI/CD pipeline for web-applications I’ve been developing ( details on a separate post). Given the only experience I have with such technologies (CI/CD Pipeline) is seeing them from marketing slide – this is an opportunity for me to learn and document my experience.

Hello Jenkins

When you think CI/CD- you’ll always going to come across Jenkins. Now, while researching – there are multiple “Jenkins” that you can install. Namely:

Jenkins – this is the legacy/ first application.

Jenkins: Blue Ocean – this is the “skinned” version of Jenkins above.

Jenkins X: modern CI/CD built for kubernetes.

Installation

I wanted to try Jenkins-X but after reading the documentation, it looks like a weekend work is not enough for me to get going as I only have an on-prem k8s running so I settled instead in installing jenkins: blueocean.

It comes as a docker-image so installing it in kubernetes is straight forward.

The only thing that took awhile to resolve is the security group which, weirdly, was not documented. The error

touch: cannot touch ‘/var/jenkins_home/copy_reference_file.log’: Permission denied
Can not write to /var/jenkins_home/copy_reference_file.log. Wrong volume permissions?

issue when trying to mount the /var/jenkins_home

Solution: Run the container under uid:gid 1000:1000

Here’s the resulting deployment manifest:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: jenkins
  namespace: jenkins
  labels:
    app: jenkins
spec:
  replicas: 1
  selector:
    matchLabels:
      app: jenkins
  template:
    metadata:
      labels:
        app: jenkins
    spec:
      containers:
      - name: jenkins
        image: jenkinsci/blueocean:1.23.2
        ports:
        - name: jenkins
          containerPort: 8080
        volumeMounts:
        - name: jenkins-home
          mountPath: /var/jenkins_home
      securityContext:
        runAsNonRoot: true
        runAsUser: 1000
        fsGroup: 1000
      volumes:
      - name: jenkins-home
        persistentVolumeClaim:
          claimName: jenkins-pvc

When the pod is up, just check the logs to get the initial password

kubectl logs <pod name> -n <namespace>

Once it’s up, just browse your ingress – and you should be greeted with the jenkins banner and setup. (set the username and plugin install)

UPDATE: After some thoughts – i’ll pause the jenkins foray for now and instead, focus on doing the CI/CD pipeline thru gitlab instead. I’ll have blogpost once I have everything setup.

Cheers.