Can't access kubernetes cluster with Istio gateway

Question

I have a k8s cluster with Istio ingress. I deployed a deployment, service, gateway and a virtual service but I still can't access my service from outside the cluster. I'm able to access my service by accessing the workers on the nodePort specified, but I'd expect that the Istio gateway will still listen on port 80 on my master but it doesn't look like that. What am I doing wrong here?

service.yaml:

apiVersion: v1
kind: Service
metadata:
  name: microservices-service
spec:
  type: NodePort
  selector:
    app: microservices-deployment
  ports:
    - port: 5001
      targetPort: 5001
      nodePort: 30007

deployment.yaml:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: microservices-deployment
  labels:
    app: microservices-deployment
spec:
  replicas: 3
  template:
    metadata:
      name: microservices-deployment
      labels:
        app: microservices-deployment
    spec:
      containers:
        - name: microservices-deployment
          image: *** private docker registry ***
          imagePullPolicy: Always
          ports:
            - containerPort: 5001
      restartPolicy: Always
      imagePullSecrets:
        - name: regcred
  selector:
    matchLabels:
      app: microservices-deployment

ingress.yaml:

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: microservices-gateway
spec:
  selector:
    istio: ingressgateway
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - "*"
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: microservices
spec:
  hosts:
  - "*"
  gateways:
  - microservices-gateway
  http:
    - match:
      route:
      - destination:
          host: *** master hostname ***
          port:
            number: 5001

Thanks a lot!

Jakub Jakub · Accepted Answer · 2020-11-12T10:22:47

I checked your configuration and everything looks set up correctly. There is only one little mistake to fix is your virtual service.

Change it from

http:
    - match:
      route:
      - destination:
          host: *** master hostname ***
          port:
            number: 5001

to

  http:
  - route:
    - destination:
        host: microservices-service
        port:
          number: 5001

And you should be able to access it with your istio gateway external-ip LoadBalancer/NodePort. More about it here.

kubectl get svc -n istio-system | grep istio-ingress

Quick example with nginx, note that I'm using LoadBalancer instead of NodePort.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx1
spec:
  selector:
    matchLabels:
      run: nginx1
  replicas: 1
  template:
    metadata:
      labels:
        run: nginx1
        app: frontend
    spec:
      containers:
      - name: nginx1
        image: nginx
        ports:
        - containerPort: 80
        lifecycle:
          postStart:
            exec:
              command: ["/bin/sh", "-c", "echo Hello nginx1 > /usr/share/nginx/html/index.html"]

---

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: frontend
spec:
  ports:
  - port: 80
    protocol: TCP
  selector:
    app: frontend

---

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: nginx-gateway
spec:
  selector:
    istio: ingressgateway
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - "*"

---

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: nginx-virtual
spec:
  gateways:
  - nginx-gateway
  hosts:
  - "*"
  http:
  - route:
    - destination:
        host: nginx.default.svc.cluster.local
        port:
          number: 80

kubectl get svc -n istio-system | grep ingress
istio-ingressgateway   LoadBalancer   xx.x.xx.xxx   xx.xx.xx.xx  15021:30880/TCP,80:31983/TCP,443:31510/TCP,15443:32267/TCP   2d2h

Test with curl

curl -v xx.xx.xx.xx/
GET / HTTP/1.1
HTTP/1.1 200 OK
Hello nginx1

Can't access kubernetes cluster with Istio gateway

1 Answers