Chapter 9. Importing a cluster

Log in to your engine cluster. The engine cluster is the cluster that contains the the multicluster engine for Kubernetes operator and the custom resource. Run the following command:

oc login

Run the following command on the engine cluster to create the project:

Note: The cluster name that is defined in CLUSTER_NAME and is also used as the cluster namespace in the .yaml file and commands:

oc new-project ${CLUSTER_NAME}

Run the following command to create the namespace:

oc label namespace ${CLUSTER_NAME} cluster.open-cluster-management.io/managedCluster=${CLUSTER_NAME}

Edit the example ManagedCluster with the following sample of YAML:

apiVersion: cluster.open-cluster-management.io/v1
kind: ManagedCluster
metadata:
  name: ${CLUSTER_NAME}
spec:
  hubAcceptsClient: true

Optional: In this release, you cannot automatically import your hub cluster to become a managed cluster, which is called a local-cluster. To manually enable the managed cluster to become a local-cluster, add metadata.labels.local-cluster: "true". See the following example YAML and ensure that the name is local-cluster. The import will fail or create unexpect results if local-cluster is not the name:

apiVersion: cluster.open-cluster-management.io/v1
kind: ManagedCluster
metadata:
  labels:
    local-cluster: "true"
    cloud: auto-detect
    vendor: auto-detect
  name: local-cluster
spec:
  hubAcceptsClient: true

Apply the YAML file with the following command:

oc apply -f managed-cluster.yaml

Use your kubeconfig or your server/token pair to create a YAML file that contains content that is similar to the following template:

apiVersion: v1
kind: Secret
metadata:
  name: auto-import-secret
stringData:
  # the following value to specify the retry times when your cluster failed to import
  autoImportRetry: "5"
  # If you are using the kubeconfig file, add the following value for the kubeconfig file
  # that has the current context set to the cluster to import:
  kubeconfig: |- <kubeconfig_file>
  # If you are using the server/token pair, add the following two values:
  server: <cluster_api_url>
  token: <Token to access the cluster>
type: Opaque

Generate the import secret in the ${CLUSTER_NAME} namespace using the kubeconfig file of the cluster you are importing. Run the following command with your path to your kubeconfig and CLUSTER_NAME:

oc apply -f auto-import-secret.yaml

Note: The auto import secret is used one time and deleted when the import process completes.

Validate the JOINED and AVAILABLE status for your imported cluster. Run the following command from the multicluster engine for Kubernetes cluster:

oc get managedcluster ${CLUSTER_NAME}

Proceed with the following steps in the separate cluster that you are importing:

Log in to the cluster that you are importing. Run the following command:

oc login

Validate the pod status on the cluster that you are importing. Run the following command:

oc get pod -n open-cluster-management-agent

Add-ons will be installed after the cluster that you are importing is AVAILABLE. Validate the pod status of add-ons on the cluster. Run the following command:

oc get pod -n open-cluster-management-agent-addon

Obtain the klusterlet-crd.yaml that was generated by the import controller on your engine cluster. Run the following command:

oc get secret ${CLUSTER_NAME}-import -n ${CLUSTER_NAME} -o jsonpath={.data.crds\\.yaml} | base64 --decode > klusterlet-crd.yaml

Obtain the import.yaml that was generated by the import controller on your engine cluster. Run the following command:

oc get secret ${CLUSTER_NAME}-import -n ${CLUSTER_NAME} -o jsonpath={.data.import\\.yaml} | base64 --decode > import.yaml

Proceed with the following steps in the separate cluster that you are importing:

Log in to the cluster that you are importing.

oc login

Apply the klusterlet-crd.yaml that you generated in the previous step. Run the following command:

oc apply -f klusterlet-crd.yaml

Apply the import.yaml file that you previously generated. Run the following command:

oc apply -f import.yaml

Validate the pod status on the cluster you are importing. Run the following command:

oc get pod -n open-cluster-management-agent

Validate JOINED and AVAILABLE status for the cluster that you are importing. From the engine cluster, run the following command:

oc get managedcluster ${CLUSTER_NAME}

Add-ons are installed after the cluster you are importing is AVAILABLE.

Validate the pod status of add-ons on the cluster you are importing. Run the following command:

oc get pod -n open-cluster-management-agent-addon