2.4. Verifying the configuration

Procedure

1. Deploy Knative Services in the namespaces of both of the tenants:

   Example command for team-alpha

   $ kn service create test-webapp -n team-alpha-1 \
       --annotation-service serving.knative.openshift.io/enablePassthrough=true \
       --annotation-revision sidecar.istio.io/inject=true \
       --env RESPONSE="Hello Serverless" \
       --image docker.io/openshift/hello-openshift

   Example command for team-bravo

   $ kn service create test-webapp -n team-bravo-1 \
       --annotation-service serving.knative.openshift.io/enablePassthrough=true \
       --annotation-revision sidecar.istio.io/inject=true \
       --env RESPONSE="Hello Serverless" \
       --image docker.io/openshift/hello-openshift

   Alternatively, use the following YAML configuration:

   apiVersion: serving.knative.dev/v1
   kind: Service
   metadata:
     name: test-webapp
     namespace: team-alpha-1
     annotations:
       serving.knative.openshift.io/enablePassthrough: "true"
   spec:
     template:
       metadata:
         annotations:
           sidecar.istio.io/inject: 'true'
       spec:
         containers:
           - image: docker.io/openshift/hello-openshift
             env:
               - name: RESPONSE
                 value: "Hello Serverless!"
   ---
   apiVersion: serving.knative.dev/v1
   kind: Service
   metadata:
     name: test-webapp
     namespace: team-bravo-1
     annotations:
       serving.knative.openshift.io/enablePassthrough: "true"
   spec:
     template:
       metadata:
         annotations:
           sidecar.istio.io/inject: 'true'
       spec:
         containers:
           - image: docker.io/openshift/hello-openshift
             env:
               - name: RESPONSE
                 value: "Hello Serverless!"

2. Deploy a curl pod for testing the connections:

   $ cat <<EOF | oc apply -f -
   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: curl
     namespace: team-alpha-1
     labels:
       app: curl
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: curl
     template:
       metadata:
         labels:
           app: curl
         annotations:
           sidecar.istio.io/inject: 'true'
       spec:
         containers:
         - name: curl
           image: curlimages/curl
           command:
           - sleep
           - "3600"
   EOF

3. Verify the configuration by using the curl command.

   Test team-alpha-1 team-alpha-1 through cluster local domain, which is allowed:

   Example command

   $ oc exec deployment/curl -n team-alpha-1 -it -- curl -v http://test-webapp.team-alpha-1:80

   Example output

   HTTP/1.1 200 OK
   content-length: 18
   content-type: text/plain; charset=utf-8
   date: Wed, 26 Jul 2023 12:49:59 GMT
   server: envoy
   x-envoy-upstream-service-time: 9
   
   Hello Serverless!

   Test the team-alpha-1 to team-alpha-1 connection through an external domain, which is allowed:

   Example command

   $ EXTERNAL_URL=$(oc get ksvc -n team-alpha-1 test-webapp -o custom-columns=:.status.url --no-headers) && \
   oc exec deployment/curl -n team-alpha-1 -it -- curl -ik $EXTERNAL_URL

   Example output

   HTTP/2 200
   content-length: 18
   content-type: text/plain; charset=utf-8
   date: Wed, 26 Jul 2023 12:55:30 GMT
   server: istio-envoy
   x-envoy-upstream-service-time: 3629
   
   Hello Serverless!

   Test the team-alpha-1 to team-bravo-1 connection through the cluster’s local domain, which is not allowed:

   Example command

   $ oc exec deployment/curl -n team-alpha-1 -it -- curl -v http://test-webapp.team-bravo-1:80

   Example output

   * processing: http://test-webapp.team-bravo-1:80
   *   Trying 172.30.73.216:80...
   * Connected to test-webapp.team-bravo-1 (172.30.73.216) port 80
   > GET / HTTP/1.1
   > Host: test-webapp.team-bravo-1
   > User-Agent: curl/8.2.0
   > Accept: */*
   >
   < HTTP/1.1 403 Forbidden
   < content-length: 19
   < content-type: text/plain
   < date: Wed, 26 Jul 2023 12:55:49 GMT
   < server: envoy
   < x-envoy-upstream-service-time: 6
   <
   * Connection #0 to host test-webapp.team-bravo-1 left intact
   RBAC: access denied

   Test the team-alpha-1 to team-bravo-1 connection through an external domain, which is allowed:

   Example command

   $ EXTERNAL_URL=$(oc get ksvc -n team-bravo-1 test-webapp -o custom-columns=:.status.url --no-headers) && \
   oc exec deployment/curl -n team-alpha-1 -it -- curl -ik $EXTERNAL_URL

   Example output

   HTTP/2 200
   content-length: 18
   content-type: text/plain; charset=utf-8
   date: Wed, 26 Jul 2023 12:56:22 GMT
   server: istio-envoy
   x-envoy-upstream-service-time: 2856
   
   Hello Serverless!

4. Delete the resources that were created for verification:

   $ oc delete deployment/curl -n team-alpha-1 && \
   oc delete ksvc/test-webapp -n team-alpha-1 && \
   oc delete ksvc/test-webapp -n team-bravo-1