I'm new to istio. I have a simple ingress gateway yaml file, and the listenling port is 26931, but after I applied the yaml, the port 26931 does not appear in the set of ports which ingress gateway expose. So am I lack of some necessary step or something else?
apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
name: batman-gateway
spec:
selector:
istio: ingressgateway
servers:
- port:
number: 26931
name: http
protocol: HTTP
hosts:
- "*"