Setup a Kubernetes Cluster

In this module, you set up a Kubernetes cluster that has Istio installed and a namespace to use throughout the tutorial.

1. Ensure you have access to a Kubernetes cluster. You can use the Google Kubernetes Engine or the IBM Cloud Kubernetes Service.

2. Create an environment variable to store the name of a namespace that you will use when you run the tutorial commands. You can use any name, for example tutorial.

   $ export NAMESPACE=tutorial
   

3. Create the namespace:

   $ kubectl create namespace $NAMESPACE
   

4. Install Istio using the demo profile.

5. The Kiali and Prometheus addons are used in this example and need to be installed. All addons are installed using:

   Zip

   $ kubectl apply -f @samples/addons@
   

6. Create a Kubernetes Ingress resource for these common Istio services using the kubectl command shown. It is not necessary to be familiar with each of these services at this point in the tutorial.

   • Grafana
   • Jaeger
   • Prometheus
   • Kiali

   The kubectl command can accept an in-line configuration to create the Ingress resources for each service:

   $ kubectl apply -f - <<EOF
   apiVersion: networking.k8s.io/v1beta1
   kind: Ingress
   metadata:
     name: istio-system
     namespace: istio-system
     annotations:
       kubernetes.io/ingress.class: istio
   spec:
     rules:
     - host: my-istio-dashboard.io
       http:
         paths:
         - path: /
           pathType: Prefix
           backend:
             serviceName: grafana
             servicePort: 3000
     - host: my-istio-tracing.io
       http:
         paths:
         - path: /
           pathType: Prefix
           backend:
             serviceName: tracing
             servicePort: 9411
     - host: my-istio-logs-database.io
       http:
         paths:
         - path: /
           pathType: Prefix
           backend:
             serviceName: prometheus
             servicePort: 9090
     - host: my-kiali.io
       http:
         paths:
         - path: /
           pathType: Prefix
           backend:
             serviceName: kiali
             servicePort: 20001
   EOF
   

7. Create a role to provide read access to the istio-system namespace. This role is required to limit permissions of the participants in the steps below.

   $ kubectl apply -f - <<EOF
   kind: Role
   apiVersion: rbac.authorization.k8s.io/v1beta1
   metadata:
     name: istio-system-access
     namespace: istio-system
   rules:
   - apiGroups: ["", "extensions", "apps"]
     resources: ["*"]
     verbs: ["get", "list"]
   EOF
   

8. Create a service account for each participant:

   $ kubectl apply -f - <<EOF
   apiVersion: v1
   kind: ServiceAccount
   metadata:
     name: ${NAMESPACE}-user
     namespace: $NAMESPACE
   EOF
   

9. Limit each participant’s permissions. During the tutorial, participants only need to create resources in their namespace and to read resources from istio-system namespace. It is a good practice, even if using your own cluster, to avoid interfering with other namespaces in your cluster.

   Create a role to allow read-write access to each participant’s namespace. Bind the participant’s service account to this role and to the role for reading resources from istio-system:

   $ kubectl apply -f - <<EOF
   kind: Role
   apiVersion: rbac.authorization.k8s.io/v1beta1
   metadata:
     name: ${NAMESPACE}-access
     namespace: $NAMESPACE
   rules:
   - apiGroups: ["", "extensions", "apps", "networking.k8s.io", "networking.istio.io", "authentication.istio.io",
                 "rbac.istio.io", "config.istio.io", "security.istio.io"]
     resources: ["*"]
     verbs: ["*"]
   ---
   kind: RoleBinding
   apiVersion: rbac.authorization.k8s.io/v1beta1
   metadata:
     name: ${NAMESPACE}-access
     namespace: $NAMESPACE
   subjects:
   - kind: ServiceAccount
     name: ${NAMESPACE}-user
     namespace: $NAMESPACE
   roleRef:
     apiGroup: rbac.authorization.k8s.io
     kind: Role
     name: ${NAMESPACE}-access
   ---
   kind: RoleBinding
   apiVersion: rbac.authorization.k8s.io/v1beta1
   metadata:
     name: ${NAMESPACE}-istio-system-access
     namespace: istio-system
   subjects:
   - kind: ServiceAccount
     name: ${NAMESPACE}-user
     namespace: $NAMESPACE
   roleRef:
     apiGroup: rbac.authorization.k8s.io
     kind: Role
     name: istio-system-access
   EOF
   

10. Each participant needs to use their own Kubernetes configuration file. This configuration file specifies the cluster details, the service account, the credentials and the namespace of the participant. The kubectl command uses the configuration file to operate on the cluster.

    Generate a Kubernetes configuration file for each participant:

    $ cat <<EOF > ./${NAMESPACE}-user-config.yaml
    apiVersion: v1
    kind: Config
    preferences: {}
    
    clusters:
    - cluster:
        certificate-authority-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
        server: $(kubectl config view -o jsonpath="{.clusters[?(.name==\"$(kubectl config view -o jsonpath="{.contexts[?(.name==\"$(kubectl config current-context)\")].context.cluster}")\")].cluster.server}")
      name: ${NAMESPACE}-cluster
    
    users:
    - name: ${NAMESPACE}-user
      user:
        as-user-extra: {}
        client-key-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
        token: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath={.data.token} | base64 --decode)
    
    contexts:
    - context:
        cluster: ${NAMESPACE}-cluster
        namespace: ${NAMESPACE}
        user: ${NAMESPACE}-user
      name: ${NAMESPACE}
    
    current-context: ${NAMESPACE}
    EOF
    

11. Set the KUBECONFIG environment variable for the ${NAMESPACE}-user-config.yaml configuration file:

    $ export KUBECONFIG=$PWD/${NAMESPACE}-user-config.yaml
    

12. Verify that the configuration took effect by printing the current namespace:

    $ kubectl config view -o jsonpath="{.contexts[?(@.name==\"$(kubectl config current-context)\")].context.namespace}"
    tutorial
    

    You should see the name of your namespace in the output.

13. If you are setting up the cluster for yourself, copy the ${NAMESPACE}-user-config.yaml file mentioned in the previous steps to your local computer, where ${NAMESPACE} is the name of the namespace you provided in the previous steps. For example, tutorial-user-config.yaml. You will need this file later in the tutorial.

    If you are an instructor, send the generated configuration files to each participant. The participants must copy their configuration file to their local computer.

Congratulations, you configured your cluster for the tutorial!

You are ready to setup a local computer.