Quickstart: Connect an existing Kubernetes cluster to Azure Arc

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Get started with Azure Arc-enabled Kubernetes by using Azure CLI or Azure PowerShell to connect an existing Kubernetes cluster to Azure Arc.

For a conceptual look at connecting clusters to Azure Arc, see Azure Arc-enabled Kubernetes agent overview. To try things out in a sample/practice experience, visit the Azure Arc Jumpstart.

Prerequisites

In addition to these prerequisites, be sure to meet all network requirements for Azure Arc-enabled Kubernetes.

  • An Azure account with an active subscription. Create a trial subscription.

  • A basic understanding of Kubernetes core concepts.

  • An identity (user or service principal) which can be used to log in to Azure CLI and connect your cluster to Azure Arc.

  • The latest version of Azure CLI.

  • The latest version of connectedk8s Azure CLI extension, installed by running the following command:

    az extension add --name connectedk8s

  • An up-and-running Kubernetes cluster. If you don't have one, you can create a cluster using one of these options:

  • At least 850 MB free for the Arc agents that will be deployed on the cluster, and capacity to use approximately 7% of a single CPU.

  • A kubeconfig file and context pointing to your cluster.

Register providers for Azure Arc-enabled Kubernetes

  1. Enter the following commands:

    az provider register --namespace Microsoft.Kubernetes
az provider register --namespace Microsoft.KubernetesConfiguration
az provider register --namespace Microsoft.ExtendedLocation

  2. Monitor the registration process. Registration may take up to 10 minutes.

    az provider show -n Microsoft.Kubernetes -o table
az provider show -n Microsoft.KubernetesConfiguration -o table
az provider show -n Microsoft.ExtendedLocation -o table

    Once registered, you should see the RegistrationState state for these namespaces change to Registered.

Create a resource group

Run the following command:

az group create --name AzureArcTest --location ChinaEast2 --output table

Output:

Location    Name
---------- ------------
chinaeast2      AzureArcTest

Connect an existing Kubernetes cluster

Run the following command to connect your cluster. This command deploys the Azure Arc agents to the cluster and installs Helm v. 3.6.3 to the .azure folder of the deployment machine. This Helm 3 installation is only used for Azure Arc, and it doesn't remove or change any previously installed versions of Helm on the machine.

In this example, the cluster's name is AzureArcTest1.

az connectedk8s connect --name AzureArcTest1 --resource-group AzureArcTest

Output:

Helm release deployment succeeded

    {
      "aadProfile": {
        "clientAppId": "",
        "serverAppId": "",
        "tenantId": ""
      },
      "agentPublicKeyCertificate": "xxxxxxxxxxxxxxxxxxx",
      "agentVersion": null,
      "connectivityStatus": "Connecting",
      "distribution": "gke",
      "id": "/subscriptions/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx/resourceGroups/AzureArcTest/providers/Microsoft.Kubernetes/connectedClusters/AzureArcTest1",
      "identity": {
        "principalId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "tenantId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "type": "SystemAssigned"
      },
      "infrastructure": "gcp",
      "kubernetesVersion": null,
      "lastConnectivityTime": null,
      "location": "chinaeast2",
      "managedIdentityCertificateExpirationTime": null,
      "name": "AzureArcTest1",
      "offering": null,
      "provisioningState": "Succeeded",
      "resourceGroup": "AzureArcTest",
      "tags": {},
      "totalCoreCount": null,
      "totalNodeCount": null,
      "type": "Microsoft.Kubernetes/connectedClusters"
    }

Tip

The above command without the location parameter specified creates the Azure Arc-enabled Kubernetes resource in the same location as the resource group. To create the Azure Arc-enabled Kubernetes resource in a different location, specify either --location <region> or -l <region> when running the az connectedk8s connect command.

Important

If deployment fails due to a timeout error, see our troubleshooting guide for details on how to resolve this issue.

Connect using an outbound proxy server

If your cluster is behind an outbound proxy server, requests must be routed via the outbound proxy server.

  1. On the deployment machine, set the environment variables needed for Azure CLI to use the outbound proxy server:

    export HTTP_PROXY=<proxy-server-ip-address>:<port>
export HTTPS_PROXY=<proxy-server-ip-address>:<port>
export NO_PROXY=<cluster-apiserver-ip-address>:<port>

  2. On the Kubernetes cluster, run the connect command with the proxy-https and proxy-http parameters specified. If your proxy server is set up with both HTTP and HTTPS, be sure to use --proxy-http for the HTTP proxy and --proxy-https for the HTTPS proxy. If your proxy server only uses HTTP, you can use that value for both parameters.

    az connectedk8s connect --name <cluster-name> --resource-group <resource-group> --proxy-https https://<proxy-server-ip-address>:<port> --proxy-http http://<proxy-server-ip-address>:<port> --proxy-skip-range <excludedIP>,<excludedCIDR> --proxy-cert <path-to-cert-file>

Note

  • Some network requests such as the ones involving in-cluster service-to-service communication need to be separated from the traffic that is routed via the proxy server for outbound communication. The --proxy-skip-range parameter can be used to specify the CIDR range and endpoints in a comma-separated way so that any communication from the agents to these endpoints do not go via the outbound proxy. At a minimum, the CIDR range of the services in the cluster should be specified as value for this parameter. For example, let's say kubectl get svc -A returns a list of services where all the services have ClusterIP values in the range 10.0.0.0/16. Then the value to specify for --proxy-skip-range is 10.0.0.0/16,kubernetes.default.svc,.svc.cluster.local,.svc.
  • --proxy-http, --proxy-https, and --proxy-skip-range are expected for most outbound proxy environments. --proxy-cert is only required if you need to inject trusted certificates expected by proxy into the trusted certificate store of agent pods.
  • The outbound proxy has to be configured to allow websocket connections.

For outbound proxy servers where only a trusted certificate needs to be provided without the proxy server endpoint inputs, az connectedk8s connect can be run with just the --proxy-cert input specified. In case multiple trusted certificates are expected, the combined certificate chain can be provided in a single file using the --proxy-cert parameter.

Note

  • --custom-ca-cert is an alias for --proxy-cert. Either parameters can be used interchangeably. Passing both parameters in the same command will honor the one passed last.

Run the connect command with the --proxy-cert parameter specified:

az connectedk8s connect --name <cluster-name> --resource-group <resource-group> --proxy-cert <path-to-cert-file>

Verify cluster connection

Run the following command:

az connectedk8s list --resource-group AzureArcTest --output table

Output:

Name           Location    ResourceGroup
------------- ----------  ---------------
AzureArcTest1  chinaeast2      AzureArcTest

Note

After onboarding the cluster, it takes around 5 to 10 minutes for the cluster metadata (cluster version, agent version, number of nodes, etc.) to surface on the overview page of the Azure Arc-enabled Kubernetes resource in Azure portal.

Tip

For help troubleshooting problems while connecting your cluster, see Diagnose connection issues for Azure Arc-enabled Kubernetes clusters.

View Azure Arc agents for Kubernetes

Azure Arc-enabled Kubernetes deploys several agents into the azure-arc namespace.

  1. View these deployments and pods using:

    kubectl get deployments,pods -n azure-arc

  2. Verify all pods are in a Running state.

    Output:

     NAME                                        READY   UP-TO-DATE   AVAILABLE   AGE
 deployment.apps/cluster-metadata-operator   1/1     1            1           13d
 deployment.apps/clusterconnect-agent        1/1     1            1           13d
 deployment.apps/clusteridentityoperator     1/1     1            1           13d
 deployment.apps/config-agent                1/1     1            1           13d
 deployment.apps/controller-manager          1/1     1            1           13d
 deployment.apps/extension-manager           1/1     1            1           13d
 deployment.apps/flux-logs-agent             1/1     1            1           13d
 deployment.apps/kube-aad-proxy              1/1     1            1           13d
 deployment.apps/metrics-agent               1/1     1            1           13d
 deployment.apps/resource-sync-agent         1/1     1            1           13d

 NAME                                            READY   STATUS    RESTARTS   AGE
 pod/cluster-metadata-operator-9568b899c-2stjn   2/2     Running   0          13d
 pod/clusterconnect-agent-576758886d-vggmv       3/3     Running   0          13d
 pod/clusteridentityoperator-6f59466c87-mm96j    2/2     Running   0          13d
 pod/config-agent-7cbd6cb89f-9fdnt               2/2     Running   0          13d
 pod/controller-manager-df6d56db5-kxmfj          2/2     Running   0          13d
 pod/extension-manager-58c94c5b89-c6q72          2/2     Running   0          13d
 pod/flux-logs-agent-6db9687fcb-rmxww            1/1     Running   0          13d
 pod/kube-aad-proxy-67b87b9f55-bthqv             2/2     Running   0          13d
 pod/metrics-agent-575c565fd9-k5j2t              2/2     Running   0          13d
 pod/resource-sync-agent-6bbd8bcd86-x5bk5        2/2     Running   0          13d

For more information about these agents, see Azure Arc-enabled Kubernetes agent overview.

Clean up resources

You can delete the Azure Arc-enabled Kubernetes resource, any associated configuration resources, and any agents running on the cluster using Azure CLI using the following command:

az connectedk8s delete --name AzureArcTest1 --resource-group AzureArcTest

If the deletion process fails, use the following command to force deletion (adding -y if you want to bypass the confirmation prompt):

az connectedk8s delete -n AzureArcTest1 -g AzureArcTest --force

This command can also be used if you experience issues when creating a new cluster deployment (due to previously created resources not being completely removed).

Note

Deleting the Azure Arc-enabled Kubernetes resource using the Azure portal removes any associated configuration resources, but does not remove any agents running on the cluster. Best practice is to delete the Azure Arc-enabled Kubernetes resource using az connectedk8s delete rather than deleting the resource in the Azure portal.

Next steps