Add-ons

Create a ManagedClusterSet resource on the hub cluster by using the instructions provided in the Creating and managing ManagedClusterSets topic of the Creating and managing ManagedClusterSets documentation. Your entry for the ManagedClusterSet should resemble the following content:

apiVersion: cluster.open-cluster-management.io/v1beta1
kind: ManagedClusterSet
metadata:
  name: <managed-cluster-set-name>

Replace managed-cluster-set-name with a name for the ManagedClusterSet that you are creating.

Note: The maximum length of the name of the Kubernetes namespace is 63 characters, so the maximum length of the <managed-cluster-set-name> is 56 characters. If the length of <managed-cluster-set-name> exceeds 56, the <managed-cluster-set-name> is truncated from the head.

After the ManagedClusterSet is created, the submariner-addon creates a namespace called <managed-cluster-set-name>-broker and deploys the Submariner broker to it.

Create the Broker configuration on the hub cluster in the <managed-cluster-set-name>-broker namespace by customizing and applying YAML content that is similar to the following example:

apiVersion: submariner.io/v1alpha1
kind: Broker
metadata:
     name: submariner-broker
     namespace: <managed-cluster-set-name>-broker
spec:
     globalnetEnabled: false

Replace managed-cluster-set-name with the name of the managed cluster.

Set the the value of globalnetEnabled to true if you want to enable Submariner Globalnet in the ManagedClusterSet.

Add one managed cluster to the ManagedClusterSet by entering the following command:

oc label managedclusters <managed-cluster-name> "cluster.open-cluster-management.io/clusterset=<managed-cluster-set-name>" --overwrite

Replace <managed-cluster-name> with the name of the managed cluster that you want to add to the ManagedClusterSet.

Replace <managed-cluster-set-name> with the name of the ManagedClusterSet to which you want to add the managed cluster.

Customize and apply YAML content that is similar to the following example:

apiVersion: submarineraddon.open-cluster-management.io/v1alpha1
kind: SubmarinerConfig
metadata:
    name: submariner
    namespace: <managed-cluster-namespace>
spec:{}

Replace managed-cluster-namespace with the namespace of your managed cluster.

Note: The name of the SubmarinerConfig must be submariner, as shown in the example.

Deploy Submariner on the managed cluster by customizing and applying YAML content that is similar to the following example:

apiVersion: addon.open-cluster-management.io/v1alpha1
kind: ManagedClusterAddOn
metadata:
     name: submariner
     namespace: <managed-cluster-name>
spec:
     installNamespace: submariner-operator

Replace managed-cluster-name with the name of the managed cluster that you want to use with Submariner.

The installNamespace field in the spec of the ManagedClusterAddOn is the namespace on the managed cluster where it installs Submariner. Currently, Submariner must be installed in the submariner-operator namespace.

After the ManagedClusterAddOn is created, the submariner-addon deploys Submariner to the submariner-operator namespace on the managed cluster. You can view the deployment status of Submariner from the status of this ManagedClusterAddOn.

Note: The name of ManagedClusterAddOn must be submariner.

After Submariner is deployed on the managed cluster, you can verify the Submariner deployment status by checking the status of submariner ManagedClusterAddOn by entering the following command:

oc -n <managed-cluster-name> get managedclusteraddons submariner -oyaml

Replace managed-cluster-name with the name of the managed cluster.

In the status of the Submariner ManagedClusterAddOn, three conditions indicate the deployment status of Submariner:

Apply an instance of the nginx service on a managed cluster that is in the ManagedClusterSet by entering the following commands:

oc -n default create deployment nginx --image=nginxinc/nginx-unprivileged:stable-alpine
oc -n default expose deployment nginx --port=8080

Export the service by creating a ServiceExport entry by entering a command with the subctl tool that is similar to the following command:

subctl export service --namespace <service-namespace> <service-name>

Replace service-namespace with the name of the namespace where the service is located. In this example, it is default.

Replace service-name with the name of the service that you are exporting. In this example, it is nginx.

See export in the Submariner documentation for more information about other available flags.

Run the following command from a different managed cluster to confirm that it can access the nginx service:

oc -n default run --generator=run-pod/v1 tmp-shell --rm -i --tty --image quay.io/submariner/nettest -- /bin/bash curl nginx.default.svc.clusterset.local:8080

Repeat those steps for other clusters from which you are removing Submariner.

Tip: You can remove the Submariner add-on from multiple clusters in the same cluster set by selecting multiple clusters and clicking Actions. Select Uninstall Submariner add-ons.

Remove the Submariner deployment for the cluster by running the following command:

oc -n <managed-cluster-namespace> delete managedclusteraddon submariner

Replace managed-cluster-namespace with the namespace of your managed cluster.

Remove the cloud resources of the cluster by running the following command:

oc -n <managed-cluster-namespace> delete submarinerconfig submariner

Replace managed-cluster-namespace with the namespace of your managed cluster.

Delete the cluster set to remove the broker details by running the following command:

oc delete managedclusterset <managedclusterset>

Replace managedclusterset with the name of your managed cluster set.

Run the following command to list any Submariner resources that remain on the cluster:

oc get cluster <CLUSTER_NAME> grep submariner

Replace CLUSTER_NAME with the name of your cluster.

Remove any resources on the list by entering the following command:

oc delete resource <RESOURCE_NAME> cluster <CLUSTER_NAME>

Replace RESOURCE_NAME with the name of the Submariner resource that you want to remove.

On the hub cluster, create a YAML file called volsync-mcao.yaml that contains content that is similar to the following example:

apiVersion: addon.open-cluster-management.io/v1alpha1
kind: ManagedClusterAddOn
metadata:
  name: volsync
  namespace: <managed-cluster-1-namespace>
spec: {}

Replace managed-cluster-1-namespace with the namespace of one of your managed clusters. This namespace is the same as the name of the managed cluster.

Note: The name must be volsync.

Apply the file to your configuration by entering a command similar to the following example:

oc apply -f volsync-mcao.yaml

Repeat the procedure for the other managed cluster.

A ManagedClusterAddOn resource should be created automatically on your hub cluster in the namespace of each corresponding managed cluster.

Configure your destination cluster.

Identify the source persistent volume claim that you want to replicate.

Note: The source persistent volume claim must be on a CSI storage class.

Create the ReplicationSource items.

Create a new persistent volume claim to contain the new data similar to the following example:

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: <pvc-name>
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 3Gi

Replace pvc-name with the name of the new persistent volume claim.

Create a ReplicationDestination custom resource that resembles the following example to specify where to restore the data:

apiVersion: volsync.backube/v1alpha1
kind: ReplicationDestination
metadata:
  name: <destination>
spec:
  trigger:
    manual: restore-once
  restic:
    repository: <restic-repo>
    destinationPVC: <pvc-name>
    copyMethod: Direct

Replace destination with the name of your replication destination CR.

Replace restic-repo with the path to your repository where the source is stored.

Replace pvc-name with the name of the new persistent volume claim where you want to restore the data. Use an existing persistent volume claim for this, rather than provisioning a new one.