Ingress

This guide covers setting up ingress on a kind cluster.

Setting Up An Ingress Controller

We can leverage KIND’s extraPortMapping config option when creating a cluster to forward ports from the host to an ingress controller running on a node.

We can also setup a custom node label by using node-labels in the kubeadm InitConfiguration, to be used by the ingress controller nodeSelector.

1. Create a cluster
2. Deploy an Ingress controller, we document Ingress NGINX here but other ingresses may work including Contour and Kong, you should follow their docs if you choose to use them.

NOTE: You may also want to consider using Gateway API instead of Ingress. Gateway API has an Ingress migration guide.

You can use blixit to test Gateway API with kind https://github.com/kubernetes-sigs/blixt#usage

Create Cluster

Create a kind cluster with extraPortMappings and node-labels.

• extraPortMappings allow the local host to make requests to the Ingress controller over ports 80/443
• node-labels only allow the ingress controller to run on a specific node(s) matching the label selector

cat <<EOF | kind create cluster --config=-
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
- role: control-plane
  kubeadmConfigPatches:
  - |
    kind: InitConfiguration
    nodeRegistration:
      kubeletExtraArgs:
        node-labels: "ingress-ready=true"
  extraPortMappings:
  - containerPort: 80
    hostPort: 80
    protocol: TCP
  - containerPort: 443
    hostPort: 443
    protocol: TCP
EOF

Ingress NGINX

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/main/deploy/static/provider/kind/deploy.yaml

The manifests contains kind specific patches to forward the hostPorts to the ingress controller, set taint tolerations and schedule it to the custom labelled node.

Now the Ingress is all setup. Wait until is ready to process requests running:

kubectl wait --namespace ingress-nginx \
  --for=condition=ready pod \
  --selector=app.kubernetes.io/component=controller \
  --timeout=90s

Refer Using Ingress for a basic example usage.

Using Ingress

The following example creates simple http-echo services and an Ingress object to route to these services.

Note, this example uses an nginx-specific Ingress annotation which may not be supported by all Ingress implementations.

kind: Pod
apiVersion: v1
metadata:
  name: foo-app
  labels:
    app: foo
spec:
  containers:
  - command:
    - /agnhost
    - netexec
    - --http-port
    - "8080"
    image: registry.k8s.io/e2e-test-images/agnhost:2.39
    name: foo-app
---
kind: Service
apiVersion: v1
metadata:
  name: foo-service
spec:
  selector:
    app: foo
  ports:
  # Default port used by the image
  - port: 8080
---
kind: Pod
apiVersion: v1
metadata:
  name: bar-app
  labels:
    app: bar
spec:
  containers:
  - command:
    - /agnhost
    - netexec
    - --http-port
    - "8080"
    image: registry.k8s.io/e2e-test-images/agnhost:2.39
    name: bar-app
---
kind: Service
apiVersion: v1
metadata:
  name: bar-service
spec:
  selector:
    app: bar
  ports:
  # Default port used by the image
  - port: 8080
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: example-ingress
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$2
spec:
  rules:
  - http:
      paths:
      - pathType: Prefix
        path: /foo(/|$)(.*)
        backend:
          service:
            name: foo-service
            port:
              number: 8080
      - pathType: Prefix
        path: /bar(/|$)(.*)
        backend:
          service:
            name: bar-service
            port:
              number: 8080
---

Apply the contents

kubectl apply -f https://kind.sigs.k8s.io/examples/ingress/usage.yaml

Now verify that the ingress works

# should output "foo-app"
curl localhost/foo/hostname
# should output "bar-app"
curl localhost/bar/hostname