Jenkins

Let's see how to run Jenkins (code, docs) in a Kubernetes cluster.

Configuration

We'll use the official Helm chart (docs):

• values.yaml

Deployment

# adds Helm chart repository
helm repo add jenkinsci https://charts.jenkins.io
helm repo update

# installs
helm upgrade --install jenkins jenkinsci/jenkins --namespace jenkins --create-namespace

# checks everything is ok
kubectl get pod -n jenkins

# uninstalls
helm uninstall jenkins -n jenkins
kubectl delete ns jenkins

Examples

Kubernetes cluster with NGINX Ingress Controller, sslip.io, cert-manager and Let's Encrypt issuers

Create the values.yaml file:

controller:
  adminUser: "admin"
  admin:
    existingSecret: ""
    userKey: jenkins-admin-user
    passwordKey: jenkins-admin-password
  resources:
    requests:
      cpu: "300m"
      memory: "512Mi"
    limits:
      cpu: "500m"
      memory: "2048Mi"

Install Jenkins:

# gets ingress controller public IP
NGINX_PUBLIC_IP=`kubectl get service -n ingress-nginx ingress-nginx-controller --output jsonpath='{.status.loadBalancer.ingress[0].ip}'`

# installs the chart
helm upgrade --install jenkins jenkinsci/jenkins -f values.yaml --namespace jenkins --create-namespace \
  --set controller.ingress.enabled=true \
  --set controller.ingress.annotations.'cert-manager\.io/cluster-issuer'=letsencrypt-prod \
  --set controller.ingress.ingressClassName=nginx \
  --set controller.ingress.hostName=jenkins.${NGINX_PUBLIC_IP}.sslip.io \
  --set controller.ingress.tls[0].secretName=jenkins-tls \
  --set controller.ingress.tls[0].hosts[0]=jenkins.${NGINX_PUBLIC_IP}.sslip.io

# retrieves the generated password
printf $(kubectl get secret --namespace jenkins jenkins -o jsonpath="{.data.jenkins-admin-password}" | base64 --decode);echo

Open the URL and log in with admin and the displayed password.