Chapter 1. Installing OpenShift Service Mesh

Procedure

1. In the OpenShift Container Platform web console, click Home Projects.
2. Click Create Project.
3. At the prompt, enter a name for the project in the Name field. For example, istio-system. The other fields provide supplementary information to the Istio resource definition and are optional.
4. Click Create. The Service Mesh Operator deploys Istio to the project you specified.

Procedure

1. In the OpenShift Container Platform web console, click Operators Installed Operators.
2. Select istio-system in the Project drop-down menu.
3. Click the Service Mesh Operator.
4. Click Istio.
5. Click Create Istio.
6. Select the istio-system project from the Namespace drop-down menu.

7. Click Create. This action deploys the Istio control plane.

   When State: Healthy appears in the Status column, Istio is successfully deployed.

Procedure

1. In the OpenShift Container Platform web console, click Home Projects.
2. Click Create Project.
3. At the prompt, you must enter a name for the project in the Name field. For example, istio-cni. The other fields provide supplementary information and are optional.
4. Click Create.

Procedure

1. In the OpenShift Container Platform web console, click Operators Installed Operators.
2. Select istio-cni in the Project drop-down menu.
3. Click the Service Mesh Operator.
4. Click IstioCNI.
5. Click Create IstioCNI.
6. Ensure that the name is default.

7. Click Create. This action deploys the Istio CNI plugin.

   When State: Healthy appears in the Status column, the Istio CNI plugin is successfully deployed.

Procedure

1. Add a label to the namespace containing the Istio control plane, for example, the istio-system system namespace.

   $ oc label namespace istio-system istio-discovery=enabled

2. Modify the Istio control plane resource to include a discoverySelectors section with the same label.

   kind: Istio
   apiVersion: sailoperator.io/v1alpha1
   metadata:
     name: default
   spec:
     namespace: istio-system
     values:
       meshConfig:
         discoverySelectors:
           - matchLabels:
               istio-discovery: enabled

3. Apply the Istio CR:

   $ oc apply -f istio.yaml

4. Ensure that all namespaces that will contain workloads that are to be part of the Service Mesh have both the discoverySelector label and, if needed, the appropriate Istio injection label.

Verification

1. Verify that the bookinfo service is available by running the following command at the CLI:

   $ oc get services -n bookinfo

   Example output

   NAME          TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
   details       ClusterIP   172.30.137.21   <none>        9080/TCP   44s
   productpage   ClusterIP   172.30.2.246    <none>        9080/TCP   43s
   ratings       ClusterIP   172.30.33.85    <none>        9080/TCP   44s
   reviews       ClusterIP   172.30.175.88   <none>        9080/TCP   44s

2. Verify that the bookinfo pods are available by running the following command at the CLI:

   $ oc get pods -n bookinfo

   Example output

   NAME                             READY   STATUS    RESTARTS   AGE
   details-v1-698d88b-km2jg         2/2     Running   0          66s
   productpage-v1-675fc69cf-cvxv9   2/2     Running   0          65s
   ratings-v1-6484c4d9bb-tpx7d      2/2     Running   0          65s
   reviews-v1-5b5d6494f4-wsrwp      2/2     Running   0          65s
   reviews-v2-5b667bcbf8-4lsfd      2/2     Running   0          65s
   reviews-v3-5b9bd44f4-44hr6       2/2     Running   0          65s

   When the Ready columns displays 2/2 the proxy sidecar was successfully injected. Confirm that Running appears in the Status column for each pod.

3. Verify that the bookinfo application running by sending a request to the bookinfo page. Run the following command at the CLI:

   $ oc exec "$(oc get pod -l app=ratings -n bookinfo -o jsonpath='{.items[0].metadata.name}')" -c ratings -n bookinfo -- curl -sS productpage:9080/productpage | grep -o "<title>.*</title>"

Procedure

1. Create the istio-ingressgateway deployment and service by running the following command at the CLI:

   $ oc apply -n bookinfo -f ingress-gateway.yaml

   Note

   This example uses a sample ingress-gateway.yaml file that is available in the Istio community repository.

2. Configure the bookinfo application to use the new gateway by applying the gateway configuration:

   $ oc apply -f https://raw.githubusercontent.com/istio/istio/release-1.23/samples/bookinfo/networking/bookinfo-gateway.yaml -n bookinfo

   Note

   To configure gateway injection with the bookinfo application, this example uses a sample gateway configuration file that must be applied in the namespace where the application is installed.

3. Use a route to expose the gateway external to the cluster:

   $ oc expose service istio-ingressgateway -n bookinfo

4. Automatically scale the pod when ingress traffic increases. This example sets the minimum replicas to 2 and the maximum replicas to 5. It also creates another replica when utilization reaches 80%.

   apiVersion: autoscaling/v2
   kind: HorizontalPodAutoscaler
   metadata:
     labels:
       istio: ingressgateway
       release: istio
     name: ingressgatewayhpa
     namespace: istio-ingress
   spec:
     maxReplicas: 5
     metrics:
     - resource:
         name: cpu
         target:
           averageUtilization: 80
           type: Utilization
       type: Resource
     minReplicas: 2
     scaleTargetRef:
       apiVersion: apps/v1
       kind: Deployment
       name: istio-ingressgateway

5. Specify the minimum number of pods that must be running on the node. This example ensures one replica is running if a pod gets restarted on a new node.

   apiVersion: policy/v1
   kind: PodDisruptionBudget
   metadata:
     labels:
       istio: ingressgateway
       release: istio
     name: ingressgatewaypdb
     namespace: istio-ingress
   spec:
     minAvailable: 1
     selector:
       matchLabels:
         istio: ingressgateway

6. Obtain the gateway host name and the URL for the product page:

   $ HOST=$(oc get route istio-ingressgateway -n bookinfo -o jsonpath='{.spec.host}')
   $ echo productpage URL: http://$HOST/productpage

7. Verify that the productpage is accessible from a web browser.

1. Prerequisites

   • You are logged in to the OpenShift Container Platform web console as cluster-admin.
   • The Red Hat OpenShift Service Mesh Operator must be installed.
   • The Istio resource must be deployed.

Procedure

1. Enable the Gateway API CRDs:

   $ oc get crd gateways.gateway.networking.k8s.io &> /dev/null ||  { oc kustomize "github.com/kubernetes-sigs/gateway-api/config/crd?ref=v1.0.0" | oc apply -f -; }

2. Create and configure a gateway using a Gateway resource and HTTPRoute resource:

   $ oc apply -f https://raw.githubusercontent.com/istio/istio/release-1.23/samples/bookinfo/gateway-api/bookinfo-gateway.yaml -n bookinfo

   Note

   To configure a gateway with the bookinfo application by using the Gateway API, this example uses a sample gateway configuration file that must be applied in the namespace where the application is installed.

3. Ensure that the Gateway API service is ready, and has an address allocated:

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

4. Retrieve the host, port and gateway URL:

   $ export INGRESS_HOST=$(oc get gtw bookinfo-gateway -n bookinfo -o jsonpath='{.status.addresses[0].value}')
   $ export INGRESS_PORT=$(oc get gtw bookinfo-gateway -n bookinfo -o jsonpath='{.spec.listeners[?(@.name=="http")].port}')
   $ export GATEWAY_URL=$INGRESS_HOST:$INGRESS_PORT

5. Obtain the gateway host name and the URL of the product page:

   $ echo "http://${GATEWAY_URL}/productpage"

6. Verify that the productpage is accessible from a web browser.