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.

    If you are in a workshop and the instructors provide a cluster for you, proceed to .

    1. Ensure you have access to a Kubernetes cluster. You can use the 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 .

    3. Create the namespace:

      1. $ kubectl create namespace $NAMESPACE

      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.

    4. using the demo profile.

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

      1. $ kubectl apply -f @samples/addons@

      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.

    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.

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

    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.

      1. $ kubectl apply -f - <<EOF
      2. kind: Role
      3. apiVersion: rbac.authorization.k8s.io/v1beta1
      4. metadata:
      5.   name: istio-system-access
      6.   namespace: istio-system
      7. rules:
      8. - apiGroups: ["", "extensions", "apps"]
      9.   verbs: ["get", "list"]
      10. EOF

    8. Create a service account for each participant:

      1. $ kubectl apply -f - <<EOF
      2. apiVersion: v1
      4. metadata:
      5.   name: ${NAMESPACE}-user
      6.   namespace: $NAMESPACE
      7. 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:

    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.

      This command assumes your cluster is named tutorial-cluster. If your cluster is named differently, replace all references with the name of your cluster.

      1. $ cat <<EOF > ./${NAMESPACE}-user-config.yaml
      2. apiVersion: v1
      3. kind: Config
      4. preferences: {}
      6. clusters:
      7. - cluster:
      8.    certificate-authority-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
      9.    server: $(kubectl config view -o jsonpath="{.clusters[?(.name==\"$(kubectl config view -o jsonpath="{.contexts[?(.name==\"$(kubectl config current-context)\")].context.cluster}")\")].cluster.server}")
      12. - name: ${NAMESPACE}-user
      13.  user:
      14.    as-user-extra: {}
      15.    client-key-data: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath='{.data.ca\.crt}')
      16.    token: $(kubectl get secret $(kubectl get sa ${NAMESPACE}-user -n $NAMESPACE -o jsonpath={.secrets..name}) -n $NAMESPACE -o jsonpath={.data.token} | base64 --decode)
      18. contexts:
      19. - context:
      20.    cluster: ${NAMESPACE}-cluster
      21.    namespace: ${NAMESPACE}
      22.    user: ${NAMESPACE}-user
      23.  name: ${NAMESPACE}
      25. current-context: ${NAMESPACE}
      26. EOF

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

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

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

      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 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.