OpenShift routes for Istio Gateways are automatically managed in Red Hat OpenShift Service Mesh. Every time an Istio Gateway is created, updated or deleted inside the service mesh, an OpenShift route is created, updated or deleted.

Enabling Automatic Route Creation

A Red Hat OpenShift Service Mesh control plane component called Istio OpenShift Routing (IOR) synchronizes the gateway route. Enable IOR as part of the control plane deployment.

If the Gateway contains a TLS section, the OpenShift Route will be configured to support TLS.

  1. In the ServiceMeshControlPlane resource, add the ior_enabled parameter and set it to true. For example, see the following resource snippet:

spec:
  istio:
    gateways:
     istio-egressgateway:
       autoscaleEnabled: false
       autoscaleMin: 1
       autoscaleMax: 5
     istio-ingressgateway:
       autoscaleEnabled: false
       autoscaleMin: 1
       autoscaleMax: 5
       ior_enabled: true

For more information, see Istio gateway configuration.

Subdomains

Red Hat OpenShift Service Mesh creates the route with the subdomain, but OpenShift Container Platform must be configured to enable it. Subdomains, for example *.domain.com, are supported but not by default. Cluster administrators can refer to Using wildcard routes for instructions on how to enable subdomains.

If the following gateway is created:

apiVersion: networking.istio.io/v1alpha3
kind: Gateway
metadata:
  name: gateway1
spec:
  selector:
    istio: ingressgateway
  servers:
  - port:
      number: 80
      name: http
      protocol: HTTP
    hosts:
    - www.bookinfo.com
    - bookinfo.example.com

Then, the following OpenShift Routes are created automatically. You can check that the routes are created with the following command.

$ oc -n <your-control-plane-namespace> get routes
Expected output
NAME           HOST/PORT             PATH  SERVICES               PORT  TERMINATION   WILDCARD
gateway1-lvlfn bookinfo.example.com        istio-ingressgateway   <all>               None
gateway1-scqhv www.bookinfo.com            istio-ingressgateway   <all>               None

If the gateway is deleted, Red Hat OpenShift Service Mesh deletes the routes. However, routes created manually are never modified by Red Hat OpenShift Service Mesh.