Development Kubernetes cluster with Kind (4) - Nginx ingress

Other posts in this series:

1. Kind cluster creation and network configuration
2. Metrics server
3. Dashboard
4. Nginx ingress

The following commands install the nginx ingress controller using the official Helm chart:

helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
helm repo update
helm show chart ingress-nginx/ingress-nginx
helm install ingress-nginx ingress-nginx/ingress-nginx --wait --namespace ingress-nginx --create-namespace --version ^4.1.0 --set-string "controller.nodeSelector.ingress-ready=true" --set controller.service.type=NodePort --set controller.service.nodePorts.http=32080 --set controller.service.nodePorts.https=32443 --set controller.metrics.enabled=true --set-string controller.podAnnotations."prometheus\.io/scrape"="true" --set-string controller.podAnnotations."prometheus\.io/port"="10254"
kubectl -n ingress-nginx wait --for=condition=ready --timeout=600s pod --selector=app.kubernetes.io/component=controller

Create example resources:

cat <<'EOF' | kubectl apply -f -
apiVersion: apps/v1
kind: Deployment
metadata:
  name: echo
  labels:
    app: echo
spec:
  replicas: 2
  selector:
    matchLabels:
      app: echo
  template:
    metadata:
      labels:
        app: echo
    spec:
      containers:
        - name: echo
          image: mendhak/http-https-echo:19
          ports:
            - containerPort: 8080
          resources:
            requests:
              cpu: 256m
              memory: 128Mi
            limits:
              cpu: 256m
              memory: 128Mi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: whoami
  labels:
    app: whoami
spec:
  replicas: 2
  selector:
    matchLabels:
      app: whoami
  template:
    metadata:
      labels:
        app: whoami
    spec:
      containers:
        - name: whoami
          image: containous/whoami:v1.5.0
          ports:
            - containerPort: 80
          resources:
            requests:
              cpu: 256m
              memory: 128Mi
            limits:
              cpu: 256m
              memory: 128Mi
---
kind: Service
apiVersion: v1
metadata:
  name: echo
spec:
  type: ClusterIP
  selector:
    app: echo
  ports:
    - protocol: "TCP"
      port: 8080
      targetPort: 8080
---
kind: Service
apiVersion: v1
metadata:
  name: whoami
spec:
  type: ClusterIP
  selector:
    app: whoami
  ports:
    - protocol: "TCP"
      port: 80
      targetPort: 80
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: echo
  annotations:
    ingress.kubernetes.io/ssl-redirect: "false"
    nginx.ingress.kubernetes.io/rewrite-target: /$2
spec:
  ingressClassName: nginx
  rules:
    - http:
        paths:
          - path: /echo(/|$)(.*)
            pathType: Prefix
            backend:
              service:
                name: echo
                port:
                  number: 8080
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: whoami
  annotations:
    ingress.kubernetes.io/ssl-redirect: "false"
    nginx.ingress.kubernetes.io/rewrite-target: /$2
spec:
  ingressClassName: nginx
  rules:
    - http:
        paths:
          - path: /whoami(/|$)(.*)
            pathType: Prefix
            backend:
              service:
                name: whoami
                port:
                  number: 80
---
EOF

Access to http://127.0.0.1:32080/echo/anything or http://127.0.0.1:32080/whoami (see containous/whoami documentation)to test.

Remember: set ingressClassName: nginx in the ingress spec, or set controller.watchIngressWithoutClass to true so all the ingress would be managed by nginx.

With the previous configuration, the nginx ingress has also been configured to expose metrics to Prometheus, that we will install in a later post; for now, to check that the metrics are being generated, we can forward the port to the metrics service:

kubectl -n ingress-nginx port-forward service/ingress-nginx-controller-metrics 10254

And explore the metrics in the URL http://127.0.0.1:10254/metrics:

# HELP go_gc_duration_seconds A summary of the pause duration of garbage collection cycles.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 2.39e-05
go_gc_duration_seconds{quantile="0.25"} 3.61e-05
go_gc_duration_seconds{quantile="0.5"} 4.96e-05
go_gc_duration_seconds{quantile="0.75"} 9.7e-05
go_gc_duration_seconds{quantile="1"} 0.0015301
go_gc_duration_seconds_sum 0.004726
go_gc_duration_seconds_count 51
...