How to create custom istio ingress gateway controller?

Question

Our GKE cluster is shared to multiple teams in company. Each team can have different public domain (and hence want to have different CA cert setup and also different ingress

Answer 1

In fact, it is very simple. Istio's ingress is just a regular Kubernetes Service of "Load Balancer" type. So, if you want to create additional IngresGateway, you can just apply your service (you can put any ports you want):

apiVersion: v1
kind: Service
metadata:
  name: istio-ingressgateway-custom
  namespace: istio-system
  annotations:
  labels:
    chart: gateways-1.0.5
    release: istio
    heritage: Tiller
    app: istio-ingressgateway
    istio: ingressgateway
spec:
  type: LoadBalancer
  selector:
    app: istio-ingressgateway
    istio: ingressgateway
  ports:
    -
      name: http2
      nodePort: 31381
      port: 80
      targetPort: 80
    -
      name: https
      nodePort: 31391
      port: 443
      targetPort: 555
    -
      name: tcp
      nodePort: 31401
      port: 31400
    -
      name: tcp-pilot-grpc-tls
      port: 15011
      targetPort: 15011
    -
      name: tcp-citadel-grpc-tls
      port: 8060
      targetPort: 8060
    -
      name: tcp-dns-tls
      port: 853
      targetPort: 853
    -
      name: http2-prometheus
      port: 15030
      targetPort: 15030
    -
      name: http2-grafana
      port: 15031
      targetPort: 15031
---

Considering you have this in file named "customingress.yaml", then you apply this using command:

kubectl apply -f customingress.yaml