Configuring Custom Ingress Ports With Cilium

This is just a note for anyone looking for a solution to this problem.

While it’s extremely easy with the Kubernetes’ newer Gateway API via listeners on Gateway resources it seems the Ingress resources were always meant to be used with (global?) default ports … mainly 80 and 443 for HTTP and HTTPS respectively. So every Ingress Controller seems to have their own “side-channel solution” that leverages some resource metadata to convey this information. For Cilium this happens to be the sparsely documented ingress.cilium.io/host-listener-port annotation.

So your Ingress definition should look something like this:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: ...
  namespace: ...
  annotations:
    ingress.cilium.io/host-listener-port: 1234
spec:
  ingressClassName: cilium
  rules:
  - http: ...