in istio, how a virtualservice defined in a namespace can use a gateway defined in another namespace

Question

If a virtualservice A is defined in namespace A using networking.istio.io, how can it use a gateway B defined in another namespace, namespace B?

Thanks

Answer 1

If it´s not in the same namespace as virtual service, you have to specify that in virtual service

Check the spec.gateways section

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: bookinfo-Mongo
  namespace: bookinfo-namespace
spec:
  gateways:
  - some-config-namespace/my-gateway # can omit the namespace if gateway is in same
                                       namespace as virtual service.

---

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: my-gateway
  namespace: some-config-namespace

There is related istio documentation about that.