Use Istio

EXPERIMENTAL

Learn how to integrate microservices managed by Istio into a DKP cluster

Istio helps you manage cloud-based deployments by providing an open-source service mesh to connect, secure, control, and observe microservices.

This topic describes how to expose an application running on the DKP cluster using the LoadBalancer (layer-4) service type.

NOTE: Usage and installation of Istio on DKP is currently a self-service feature.

Before you begin

Before you begin, verify the following:

  • You must have access to a Linux, macOS, or Windows computer with a supported operating system version.

  • You must have a properly deployed and running cluster.

Deploy Istio using DKP

Review the list of available applications to obtain the current ‘APP NAME’ for the Istio application, as you will need this name later in this procedure.

  1. Enable the deployment of Istio to your existing attached cluster by creating an AppDeployment resource.

  2. Within the AppDeployment, define the appRef to specify which App will be enabled:

    cat <<EOF | kubectl apply -f -
    apiVersion: apps.kommander.d2iq.io/v1alpha2
    kind: AppDeployment
    metadata:
      name: istio
      namespace: ${WORKSPACE_NAMESPACE}
    spec:
      appRef:
        name: istio-1.11.6
        kind: ClusterApp
    EOF
    
  3. Create the resource in the workspace you just created, which instructs Kommander to deploy the AppDeployment to the KommanderClusters in the same workspace.

NOTE: The appRef.name must match the app name from the list of available applications.

Download the Istio command line utility

  1. Store a local environment variable containing the current Istio version running in your cluster:

    export KONVOY_ISTIO_VERSION="$(kubectl get clusteraddons istio -o go-template='{{ .spec.chartReference.version }}')"
    
  2. Pull a copy of the corresponding Istio command line to your system:

    curl -L https://istio.io/downloadIstio | ISTIO_VERSION=${KONVOY_ISTIO_VERSION} sh -
    
  3. Change to the Istio directory and set your PATH environment variable by running the following commands:

    cd istio*
    export PATH=$PWD/bin:$PATH
    
  4. You should now be able to run the following istioctl command and view the subsequent output:

    istioctl version
    
    client version: <your istio version here>
    control plane version: <your istio version here>
    data plane version: <your istio version here> (1 proxies)
    

Deploy a sample application on Istio

The Istio BookInfo sample application is composed of four separate microservices that demonstrate various Istio features.

  1. Deploy the sample bookinfo application on the Kubernetes cluster by running the following commands:

    IMPORTANT: Ensure your dkp configuration references the cluster where you deployed Istio by setting the KUBECONFIG environment variable, or using the --kubeconfig flag, in accordance with Kubernetes conventions.

    kubectl apply -f <(istioctl kube-inject -f samples/bookinfo/platform/kube/bookinfo.yaml)
    kubectl apply -f samples/bookinfo/networking/bookinfo-gateway.yaml
    
  2. Get the URL of the load balancer created on AWS for this service by running the following command:

    kubectl get svc istio-ingressgateway -n istio-system
    

    The command displays output similar to the following:

    NAME                   TYPE           CLUSTER-IP    EXTERNAL-IP                                                               PORT(S)                                                                                                                                      AGE
    istio-ingressgateway   LoadBalancer   10.0.29.241   a682d13086ccf11e982140acb7ee21b7-2083182676.us-west-2.elb.amazonaws.com   15020:30380/TCP,80:31380/TCP,443:31390/TCP,31400:31400/TCP,15029:30756/TCP,15030:31420/TCP,15031:31948/TCP,15032:32061/TCP,15443:31232/TCP   110s
    
  3. Open a web browser and navigate to the external IP address for the load balancer to access the application.

    For example, the external IP address in the sample output is a682d13086ccf11e982140acb7ee21b7-2083182676.us-west-2.elb.amazonaws.com, enabling you to access the application using the following URL: http://a682d13086ccf11e982140acb7ee21b7-2083182676.us-west-2.elb.amazonaws.com/productpage

  4. Follow the steps in the Istio BookInfo Application documentation to understand the different Istio features.