Set up a Kubernetes Cluster

{{< boilerplate work-in-progress >}}

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

{{< warning >}} If you are in a workshop and the instructors provide a cluster for you, proceed to setting up your local computer. {{</ warning >}}

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.

   {{< text bash >}} $ export NAMESPACE=tutorial {{< /text >}}

3. Create the namespace:

   {{< text bash >}} $ kubectl create namespace $NAMESPACE {{< /text >}}

   {{< tip >}} If you are an instructor, you should allocate a separate namespace per each participant. The tutorial supports work in multiple namespaces simultaneously by multiple participants. {{< /tip >}}

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:

   {{< text bash >}} $ kubectl apply -f @samples/addons@ {{< /text >}}

   {{< tip >}} If there are errors trying to install the addons, try running the command again. There may be some timing issues which will be resolved when the command is run again. {{< /tip >}}

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:

   {{< text bash >}} $ kubectl apply -f - <<EOF apiVersion: networking.k8s.io/v1 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: service: name: grafana port: number: 3000
   • host: my-istio-tracing.io http: paths:
     • path: / pathType: Prefix backend: service: name: tracing port: number: 9411
   • host: my-istio-logs-database.io http: paths:
     • path: / pathType: Prefix backend: service: name: prometheus port: number: 9090
   • host: my-kiali.io http: paths:
     • path: / pathType: Prefix backend: service: name: kiali port: number: 20001 EOF {{< /text >}}

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.

   {{< text bash >}} $ kubectl apply -f - <<EOF kind: Role apiVersion: rbac.authorization.k8s.io/v1 metadata: name: istio-system-access namespace: istio-system rules:

   • apiGroups: ["", "extensions", "apps"] resources: ["*"] verbs: ["get", "list"] EOF {{< /text >}}

8. Create a service account for each participant:

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

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:

   {{< text bash >}} $ kubectl apply -f - <<EOF kind: Role apiVersion: rbac.authorization.k8s.io/v1 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/v1 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/v1 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 {{< /text >}}

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:

    {{< tip >}} This command assumes your cluster is named tutorial-cluster. If your cluster is named differently, replace all references with the name of your cluster. {{</ tip >}}

    {{< text bash >}} $ 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 {{< /text >}}

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

    {{< text bash >}} $ export KUBECONFIG=$PWD/${NAMESPACE}-user-config.yaml {{< /text >}}

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

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

    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 set up a local computer.