Chapter 2. Getting traffic into a mesh

Procedure

1. Create namespace called httpbin by running the following command:

   $ oc create namespace httpbin

2. Enable sidecar injection in the namespace. If you are using the InPlace upgrade strategy, run the following command:

   $ oc label namespace httpbin istio-injection=enabled

   Note

   If you are using the RevisionBased upgrade strategy, run the following commands:

   1. To find your <revision-name>, run the following command:

      $ oc get istiorevisions.sailoperator.io

      You will get an output similar to the following example:

   NAME      TYPE    READY   STATUS    IN USE   VERSION   AGE
   default   Local   True    Healthy   True    v1.24.3   3m33s

   1. Label the namespace with the revision name to enable sidecar injection:

      $ oc label namespace httpbin istio.io/rev=default

3. Deploy a sample service named httpbin by running the following command:

   $ oc apply -n httpbin -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/httpbin/httpbin.yaml

4. Create a YAML file named httpbin-gw.yaml that defines an Istio Gateway resource. This resource configures gateway proxies to expose port 80 (HTTP) for the host, httpbin.example.com.

   apiVersion: networking.istio.io/v1
   kind: Gateway
   metadata:
     name: httpbin-gateway
     namespace: httpbin
   spec:
     selector:
       istio: <gateway_name> 

   1

   
     servers:
     - port:
         number: 80
         name: http
         protocol: HTTP
       hosts:
       - httpbin.example.com 

   2

   1

   Set the selector to the unique label or set of labels specified in the pod template of the gateway proxy Deployment. By default, the Istio Gateway resource configuration will apply to matching gateway pods in all namespaces.

   2

   Using the hosts field, specify a list of addresses that can be used by clients when attempting to access a mesh service at the associated port.

5. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-gw.yaml

6. Create a YAML file named httpbin-vs.yaml for a VirtualService. The VirtualService defines the rules that route traffic from the gateway proxy to the httpbin service.

   apiVersion: networking.istio.io/v1
   kind: VirtualService
   metadata:
     name: httpbin
     namespace: httpbin
   spec:
     hosts:
     - httpbin.example.com 

   1

   
     gateways:
     - httpbin-gateway 

   2

   
     http:
     - match:
       - uri:
           prefix: /status
       - uri:
           prefix: /headers
       route:
       - destination: 

   3

   
           port:
             number: 8000
           host: httpbin

   1

   Specify the hosts that the routing rules of the VirtualService will be applied to. The hosts specified must be exposed by the Istio Gateway resource the VirtualService is bound to.

   2

   Bind the VirtualService to the Istio Gateway resource created in the previous step by adding the Gateway name to the list of gateways.

   3

   Route matching traffic to the httpbin service deployed earlier by defining a destination that includes the host and port of the httpbin Service.

7. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-vs.yaml

8. For verification purposes, create a namespace for a curl client by running the following command:

   $ oc create namespace curl

9. Deploy the curl client by running the following command:

   $ oc apply -n curl -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/curl/curl.yaml

10. Set a CURL_POD variable with the name of the curl pod by running the following command:

    $ CURL_POD=$(oc get pods -n curl -l app=curl -o jsonpath='{.items[*].metadata.name}')

11. Using the curl client, send a request to the /headers endpoint of the httpbin application through the ingress gateway Service resource. Set the Host header of the request to httpbin.example.com to match the host that the Istio Gateway and VirtualService resources specify. Run the following curl command to send the request:

    $ oc exec $CURL_POD -n curl -- \
      curl -s -I \
        -H Host:httpbin.example.com \
        <gateway_name>.<gateway_namespace>.svc.cluster.local/headers

12. The response should have a 200 OK HTTP status indicating that the request was successful.

    HTTP/1.1 200 OK
    server: istio-envoy
    ...

13. Send a curl request to an endpoint that does not have a corresponding URI prefix match defined in the httpbin VirtualService by running the following command:

    $ oc exec $CURL_POD -n curl -- \
      curl -s -I \
        -H Host:httpbin.example.com \
        <gateway_name>.<gateway_namespace>.svc.cluster.local/get

    The response should return a 404 Not Found status. This is expected because the /get endpoint does not have a matching URI prefix in the httpbin VirtualService resource.

    HTTP/1.1 404 Not Found
    server: istio-envoy
    ...

14. Expose the gateway proxy to traffic outside the cluster by setting the Service type to LoadBalancer:

    $ oc patch service <gateway_name> -n <gateway_namespace> -p '{"spec": {"type": "LoadBalancer"}}'

    Note

    A gateway can also be exposed to traffic outside the cluster by using OpenShift Routes. For more information, see "Exposing a gateway to traffic outside the cluster using OpenShift Routes".

15. Verify that httpbin service can be accessed from outside the cluster when using the external hostname or IP address of the gateway Service resource. Ensure that you set the INGRESS_HOST variable appropriately for the environment that your cluster is running in.

    1. If the cluster runs on AWS, set the INGRESS_HOST variable by running the following command:

       $ INGRESS_HOST=$(oc get service <gateway_name> -n <gateway_namespace> -o jsonpath='{.status.loadBalancer.ingress[0].hostname}')

    2. If the cluster runs on GCP or Azure, set the INGRESS_HOST variable by running the following command:

       $ INGRESS_HOST=$(oc get service <gateway_name> -n <gateway_namespace> -o jsonpath='{.status.loadBalancer.ingress[0].ip}')

    3. Send a curl request to the httpbin service using the host of the gateway by running the following command:

       $ curl -s -I -H Host:httpbin.example.com http://$INGRESS_HOST/headers

16. Verify that the response has the HTTP/1.1 200 OK status, which indicates that the request was successful.

Procedure

1. Create a namespace called httpbin by running the following command:

   $ oc create namespace httpbin

2. When using sidecar injection instead of ambient mode, you must enable the sidecar injection in the namespace:

   1. For the InPlace upgrade strategy, run the following command:

      $ oc label namespace httpbin istio-injection=enabled

   2. For the RevisionBased upgrade strategy, run the following command:

      $ oc label namespace httpbin istio.io/rev=<revision-name>

3. Deploy a sample service named httpbin by running the following command:

   $ oc apply -n httpbin -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/httpbin/httpbin.yaml

4. Create a YAML file named httpbin-gw.yaml that defines a Kubernetes Gateway resource, similar to the following example:

   apiVersion: gateway.networking.k8s.io/v1
   kind: Gateway
   metadata:
     name: httpbin-gateway
     namespace: httpbin
   spec:
     gatewayClassName: istio
     listeners:
     - name: default
       hostname: "httpbin.example.com"
       port: 80
       protocol: HTTP
       allowedRoutes:
         namespaces:
           from: All

   "httpbin.example.com"

   Specifies the virtual hostname that clients use when attempting to access a mesh service on the associated port.

   The HTTPRoute resource specifies the rules that route traffic from the gateway proxy to the httpbin service.

5. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-gw.yaml

6. Create a YAML file named httpbin-ingress-hr.yaml that defines an HTTPRoute resource for the ingress gateway, similar to the following example:

   apiVersion: gateway.networking.k8s.io/v1
   kind: HTTPRoute
   metadata:
     name: httpbin-ingress
     namespace: httpbin
   spec:
     parentRefs:
     - name: httpbin-gateway
       namespace: httpbin
     hostnames:
     - "httpbin.example.com"
     rules:
     - matches:
       - path:
           type: PathPrefix
           value: /status
       - path:
           type: PathPrefix
           value: /headers
     - backendRefs:
       - name: httpbin
         port: 8000

   • spec.parentRefs binds the HTTPROUTE resource to the Kubernetes Gateway resource that was created in the earlier step.
   • spec.rules.backendRefs routes the matching traffic to the httpbin service by defining a backendRefs that includes the name and port of the httpbin service.

   The HTTPRoute resource specifies the rules that route traffic from the gateway proxy to the httpbin service.

7. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-ingress-hr.yaml

8. Ensure that the Gateway API service is ready, and that an address is allocated to the service, by running the following command:

   $ oc wait --for=condition=programmed gtw httpbin-gateway -n httpbin

Verification

1. Create a namespace for a curl client by running the following command:

   $ oc create namespace curl

2. Deploy a curl client by running the following command:

   $ oc apply -n curl -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/curl/curl.yaml

3. Set a CURL_POD variable with the name of the curl pod by running the following command:

   $ CURL_POD=$(oc get pods -n curl -l app=curl -o jsonpath='{.items[*].metadata.name}')

4. Using the curl client, send a request to the /headers endpoint of the httpbin application through the ingress gateway Service resource. Set the Host header of the request to httpbin.example.com to match the host that the Kubernetes Gateway and HTTPROUTE resources specify. Send the curl request by running the following command:

   $ oc exec $CURL_POD -n curl -- \
     curl -s -I \
       -H Host:httpbin.example.com \
       <gateway_name>-istio.<gateway_namespace>.svc.cluster.local/headers

   The response should return a 200 OK HTTP status, which indicates that the request was successful, similar to the following example:

   HTTP/1.1 200 OK
   server: istio-envoy
   ...

5. Send a curl request to an endpoint that does not have a corresponding Uniform Resource Identifier (URI) prefix match defined in the httpbin HTTPROUTE by running the following command:

   $ oc exec $CURL_POD -n curl -- \
     curl -s -I \
       -H Host:httpbin.example.com \
       <gateway_name>-istio.<gateway_namespace>.svc.cluster.local/get

   The response returns a 404 Not Found status, as expected, because the /get endpoint does not have a matching URI prefix in the httpbin HTTPROUTE resource, similar to the following example:

   HTTP/1.1 404 Not Found
   server: istio-envoy
   ...

6. Expose the gateway proxy to traffic outside the cluster by setting the Service type to LoadBalancer. Run the following command:

   $ oc patch service <gateway_name>-istio -n <gateway_namespace> -p '{"spec": {"type": "LoadBalancer"}}'

   Note

   A gateway can also be exposed to traffic outside the cluster by using OpenShift Routes. For more information, see "Exposing a gateway to traffic outside the cluster using OpenShift Routes".

7. Verify that the httpbin service can be accessed from outside the cluster when using the external hostname or IP address of the gateway Service resource. Ensure that you set the INGRESS_HOST variable appropriately for the environment in which your cluster is running.

   1. Set the INGRESS_HOST variable by running the following command:

      $ export INGRESS_HOST=$(oc get gtw <gateway_name> -n <gateway_namespace> -o jsonpath='{.status.addresses[0].value}')

   2. Set the INGRESS_PORT variable by running the following command:

      $ INGRESS_PORT=$(oc get gtw <gateway_name> -n <gateway_namespace> -o jsonpath='{.spec.listeners[?(@.name=="http")].port}')

   3. Using the gateway host, send a curl request to the httpbin service by running the following command:

      $ curl -s -I -H Host:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/headers

8. Verify that the response has the HTTP/1.1 200 OK status, which indicates that the request was successful.

Procedure

1. Create a namespace called httpbin by running the following command:

   $ oc create namespace httpbin

2. Apply the label for ambient mode by running the following command:

   $ oc label namespace httpbin istio.io/dataplane-mode=ambient

3. Deploy a sample service named httpbin by running the following command:

   $ oc apply -n httpbin -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/httpbin/httpbin.yaml

4. Deploy a waypoint proxy by creating a YAML file named httpbin-waypoint.yaml, similar to the following example:

   apiVersion: gateway.networking.k8s.io/v1
   kind: Gateway
   metadata:
     name: httpbin-waypoint
     namespace: httpbin
     labels:
       istio.io/waypoint-for: service
   spec:
     gatewayClassName: istio-waypoint
     listeners:
     - name: mesh
       port: 15008
       protocol: HBONE

5. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-waypoint.yaml

6. Enable ingress waypoint routing on the httpbin service by running the following command:

   $ oc label service httpbin -n httpbin istio.io/ingress-use-waypoint=true

   The label ensures that traffic from the ingress gateway routes through the waypoint proxy and the Layer 7 (L7) policies configured on the waypoint proxy are applied to the ingress traffic, before it reaches the httpbin service.

7. Apply the waypoint label to the namespace so that all the services inside the namespace routes through the waypoint, by running the following command:

   $ oc label ns httpbin istio.io/use-waypoint=httpbin-waypoint

8. Create a YAML file named httpbin-gw.yaml that defines a Kubernetes Gateway resource. This resource configures gateway proxies to expose port 80 (HTTP) for the host, httpbin.example.com.

   apiVersion: gateway.networking.k8s.io/v1
   kind: Gateway
   metadata:
     name: httpbin-gateway
     namespace: httpbin
   spec:
     gatewayClassName: istio
     listeners:
     - name: default
       hostname: "httpbin.example.com"
       port: 80
       protocol: HTTP
       allowedRoutes:
         namespaces:
           from: All

   "httpbin.example.com"

   Specifies the virtual hostname that clients use when attempting to access a mesh service on the associated port.

9. Apply the YAML file by running the following command:

   $ oc apply -f httpbin-gw.yaml

10. Create a YAML file named httpbin-ingress-hr.yaml that defines an HTTPRoute resource for the ingress gateway, similar to the following example:

    apiVersion: gateway.networking.k8s.io/v1
    kind: HTTPRoute
    metadata:
      name: httpbin-ingress
      namespace: httpbin
    spec:
      parentRefs:
      - name: httpbin-gateway
        namespace: httpbin
      hostnames:
      - "httpbin.example.com"
      rules:
      - backendRefs:
        - name: httpbin
          port: 8000

    • spec.parentRefs binds the HTTPROUTE resource to the Kubernetes Gateway resource that was created in the earlier step.
    • spec.rules.backendRefs routes the matching traffic to the httpbin service by defining a backendRefs that includes the name and port of the httpbin service.

    The HTTPRoute resource specifies the rules that route traffic from the gateway proxy to the httpbin service.

11. Apply the YAML file by running the following command:

    $ oc apply -f httpbin-ingress-hr.yaml

12. Create a YAML file named httpbin-waypoint-hr.yaml that defines an HTTPRoute resource for the waypoint proxy.

    apiVersion: gateway.networking.k8s.io/v1
    kind: HTTPRoute
    metadata:
      name: httpbin-waypoint-route
      namespace: httpbin
    spec:
      parentRefs:
      - group: ""
        kind: service
        name: httpbin
        namespace: httpbin
      rules:
      - matches:
        - path:
            type: PathPrefix
            value: /status
        - path:
            type: PathPrefix
            value: /headers
        backendRefs:
        - name: httpbin
          port: 8000

    • spec.parentRefs binds the HTTPRoute resource to the httpbin service. When combined with the istio.io/ingress-use-waypoint=true label on the service, the HTTPRoute configures the L7 routing rules that the waypoint proxy will enforce for traffic destined to that service.
    • spec.rules.backendRefs routes the matching traffic to the httpbin service by defining a backendRefs that includes the name and port of the httpbin service.

13. Apply the YAML file by running the following command:

    $ oc apply -f httpbin-waypoint-hr.yaml

    Note

    In this example use case, traffic from the ingress gateway flows through the waypoint proxy because of the istio.io/ingress-use-waypoint=true label. The HTTPRoute resource then applies path-based routing policies before the traffic reaches the httpbin service.

14. Ensure that the waypoint proxy is ready by running the following command:

    $ oc wait --for=condition=programmed gtw httpbin-waypoint -n httpbin

Verification

1. Create a namespace for a curl client by running the following command:

   $ oc create namespace curl

2. Deploy a curl client by running the following command:

   $ oc apply -n curl -f https://raw.githubusercontent.com/openshift-service-mesh/istio/refs/heads/master/samples/curl/curl.yaml

3. Apply the label for ambient mode to the curl namespace by running the following command:

   $ oc label namespace curl istio.io/dataplane-mode=ambient

4. Set a CURL_POD variable with the name of the curl pod by running the following command:

   $ CURL_POD=$(oc get pods -n curl -l app=curl -o jsonpath='{.items[*].metadata.name}')

5. Using the curl client, send a request to the /headers endpoint of the httpbin application through the ingress gateway Service resource. Set the Host header of the request to httpbin.example.com to match the host that the Kubernetes Gateway and HTTPROUTE resources specify. Send the curl request by running the following command:

   $ oc exec $CURL_POD -n curl -- \
     curl -s -I \
       -H Host:httpbin.example.com \
       httpbin-gateway-istio.httpbin.svc.cluster.local/headers

   The response should return a 200 OK HTTP status, which indicates that the request was successful, similar to the following example:

   HTTP/1.1 200 OK
   server: istio-envoy
   ...

6. Send a curl request to an endpoint that does not have a corresponding Uniform Resource Identifier (URI) prefix match defined in the httpbin HTTPROUTE by running the following command:

   $ oc exec $CURL_POD -n curl -- \
     curl -s -I \
       -H Host:httpbin.example.com \
       httpbin-gateway-istio.httpbin.svc.cluster.local/get

   The response returns a 404 Not Found status, as expected, because the /get endpoint does not have a matching URI prefix in the httpbin HTTPROUTE resource, similar to the following example:

   HTTP/1.1 404 Not Found
   server: istio-envoy
   ...

7. Expose the gateway proxy to traffic outside the cluster by setting the Service type to LoadBalancer. Run the following command:

   $ oc patch service httpbin-gateway-istio -n httpbin -p '{"spec": {"type": "LoadBalancer"}}'

   Note

   A gateway can also be exposed to traffic outside the cluster by using OpenShift Routes. For more information, see "Exposing a gateway to traffic outside the cluster using OpenShift Routes".

8. Verify that the httpbin service can be accessed from outside the cluster when using the external hostname or IP address of the gateway Service resource. Ensure that you set the INGRESS_HOST variable appropriately for the environment in which your cluster is running.

   1. Set the INGRESS_HOST variable by running the following command:

      $ export INGRESS_HOST=$(oc get gtw httpbin-gateway -n httpbin -o jsonpath='{.status.addresses[0].value}')

   2. Set the INGRESS_PORT variable by running the following command:

      $ INGRESS_PORT=$(oc get gtw httpbin-gateway -n httpbin -o jsonpath='{.spec.listeners[?(@.name=="http")].port}')

   3. Using the gateway host, send a curl request to the httpbin service by running the following command:

      $ curl -s -I -H Host:httpbin.example.com http://$INGRESS_HOST:$INGRESS_PORT/headers

9. Verify that the response has the HTTP/1.1 200 OK status, which indicates that the request was successful.