Make gRPC server available outside cluster using Traefik loadbalancer

[huberts90]

Hi,
I am trying to set up a gRPC server inside cluster listening on port 80, being available in insecure mode.

1. k3d is created with 8081:80@loadbalancer port mapping.
2. Service configuration

apiVersion: v1
kind: Service
metadata:
  name: signer
spec:
  ports:
    - name: grpc
      port: 80
      protocol: TCP
      targetPort: 80
  selector:
    app: signer
  type: ClusterIP

3. Ingress configuration

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: signer
  namespace: signer
  annotations:
    traefik.ingress.kubernetes.io/router.entrypoints: web
    ingress.kubernetes.io/protocol: h2c
spec:
  rules:
  - host: signer
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: signer
            port:
              number: 80

4. Connection made from a docker container

docker run --rm -it \
    --add-host "signer:<load-balancer-ip>" \
    --network k3d-signer \
    ...

5. Unfortunately I get an error: gRPC GetSignStream failed with Unknown: unexpected HTTP status code received from server: 500 (Internal Server Error); transport: received unexpected content-type "text/plain; charset=utf-8
6. The same configuration as above is working successfully for HTTP connection (without ingress.kubernetes.io/protocol: h2c)
7. How can I set gRPC to be available on port e.q. 8000 ? Do I need port mapping 8000:8000@loadbalancer ? Do I need IngressRoute ?

[huberts90]

Can I ask for any tips?

[iwilltry42]

Hey @huberts90 👋
Which port do you use for the request? Since your test container and the cluster (and loadbalancer) are in the same docker network and you're not connecting via host address, you'll have to use the container port, not the mapped port 🤔