Q-04 — Ingress (CKA 2025)

📌 Question

Create a new Ingress resource named echo in the echo-sound namespace. Expose the Service echoserver-service on:

http://example.org/echo

using Service port 8080. The command:

curl -o /dev/null -s -w "%{http_code}\n" http://example.org/echo

should return 200.

❗ Why we will NOT use Regex here

The exam URL provided is:

http://example.org/echo

NOT:

http://example.org/echo/test
http://example.org/echo/anything/else

Since the URL contains no subpaths, Kubernetes expects a simple path rule.

Therefore:

✔ NO regex required

✔ NO capture groups required

✔ NO `(.*)` patterns

✔ Only `/echo` is matched

Regex is only used when the path must match dynamic segments, which is not the case here.

🟦 If the Ingress Controller is nginx (most common in exam)

Nginx does NOT automatically strip the prefix /echo. So the backend would receive:

/echo

But echo-server expects:

So we must add a rewrite annotation:

nginx.ingress.kubernetes.io/rewrite-target: /

✅ Correct Ingress manifest (nginx)

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: echo
  namespace: echo-sound
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  ingressClassName: nginx
  rules:
  - host: example.org
    http:
      paths:
      - path: /echo
        pathType: Prefix
        backend:
          service:
            name: echoserver-service
            port:
              number: 8080

🟩 If the Ingress Controller is Traefik

Traefik automatically strips the prefix /echo. So no rewrite annotation is needed.

✅ Correct Ingress manifest (Traefik)

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: echo
  namespace: echo-sound
spec:
  ingressClassName: traefik
  rules:
  - host: example.org
    http:
      paths:
      - path: /echo
        pathType: Prefix
        backend:
          service:
            name: echoserver-service
            port:
              number: 8080

🏗 Full Lab Setup (Deployment + Service + Ingress)

This allows you to fully test the question.

1️⃣ Namespace

apiVersion: v1
kind: Namespace
metadata:
  name: echo-sound

2️⃣ Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  name: echoserver-deployment
  namespace: echo-sound
spec:
  replicas: 1
  selector:
    matchLabels:
      app: echoserver
  template:
    metadata:
      labels:
        app: echoserver
    spec:
      containers:
      - name: echoserver
        image: k8s.gcr.io/echoserver:1.4
        ports:
        - containerPort: 8080

3️⃣ Service

apiVersion: v1
kind: Service
metadata:
  name: echoserver-service
  namespace: echo-sound
spec:
  selector:
    app: echoserver
  ports:
  - port: 8080
    targetPort: 8080

4️⃣ Ingress (Nginx version – most likely for exam)

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: echo
  namespace: echo-sound
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  ingressClassName: nginx
  rules:
  - host: example.org
    http:
      paths:
      - path: /echo
        pathType: Prefix
        backend:
          service:
            name: echoserver-service
            port:
              number: 8080

🧪 Testing

With DNS:

curl -o /dev/null -s -w "%{http_code}\n" http://example.org/echo

If it returns 200, you succeeded.

Without DNS (common in labs):

curl -o /dev/null -s -w "%{http_code}\n" -H "Host: example.org" http://NODE_IP:NODE_PORT/echo