Attaching an existing cluster

If you have an existing cluster, you can attach the cluster to your VMware Tanzu Mission Control organization. Attaching your cluster allows you to manage the cluster on Tanzu Mission Control.

Attaching a cluster involves steps on Tanzu Mission Control and on your cluster.

1. On Tanzu Mission Control, register the cluster name with the Tanzu Mission Control agent service.
2. On the cluster, install the cluster agent extensions.
3. On Tanzu Mission Control, verify the connection.

For more information about what happens when you attach a cluster, see What Happens When You Attach a Cluster in VMware Tanzu Mission Control Concepts.

What to do first

This task requires the following:

• A running cluster that was not provisioned through Tanzu Mission Control. If you don’t have one, you can skip this section.

• You have the appropriate permissions to attach the cluster.

  • On Tanzu Mission Control, you must be associated with the clustergroup.edit role on the cluster group in which you want to put the new cluster.
  • On the cluster, you must have admin permissions to install and run the cluster agent extensions.

Attach an existing cluster

Do the following to attach an existing cluster to Tanzu Mission Control:

1. In the left navigation pane of the Tanzu Mission Control console, click Clusters.

   

2. On the Clusters page, click Attach Cluster.

3. Select the cluster group in which you want to register the cluster, and enter a name for the cluster.

   The cluster name appears in the list of clusters on the Clusters page.

4. (Optional) provide a description and one or more labels.

5. Click Next.

   When you click Next, Tanzu Mission Control generates a YAML manifest specifically for your cluster, and displays the kubectl command to run the manifest.

   Note

   The YAML manifest generated by Tanzu Mission Control contains credentials that permit the cluster to attach to the cluster agent service. These credentials are valid for 48 hours. If you attempt to install the agent extensions after the credentials lapse, the attachment fails and your cluster remains indefinitely in Pending status in the Tanzu Mission Control console.

   If you suspect you are in this situation, locate your cluster on the Clusters page of the Tanzu Mission Control console. Select the cluster and click Detach to remove the cluster from the cluster agent service registry. Then, in your cluster, delete the vmware-system-tmc namespace and the following CRDs:

   • extensions.clusters.tmc.cloud.vmware.com

   • agents.clusters.tmc.cloud.vmware.com

   You can then work through the procedure again to attach the cluster.

6. Copy the kubectl command.

7. Open a command window and connect to your cluster with kubectl.

8. Run the kubectl command that you copied in Tanzu Mission Control against your cluster in your kubectl command window.

   The YAML manifest runs a small set of extensions in your cluster to connect it with the cluster agent service.

9. After the extensions are up and running in your cluster, return to the Tanzu Mission Control console and click Verify Connection.

   Although optional, it is a good idea to verify that Tanzu Mission Control and the cluster are communicating with each other.