Manage Your Management Clusters

This topic explains how to manage multiple management clusters from the same bootstrap machine, including management clusters deployed by Tanzu Kubernetes Grid to vSphere, Azure, or Amazon Web Services (AWS) and vSphere with Tanzu Supervisor Clusters designated as Tanzu Kubernetes Grid management clusters.

List Management Clusters and Change Context

To list available management clusters and see which one you are currently logged in to, run tanzu login on your bootstrap machine:

To change your current login context, use your up- and down-arrow keys to highlight the new management cluster and then press Enter.
To retain your current context, press Enter without changing the highlighting.

For example, if you have two management clusters, my-vsphere-mgmt-cluster and my-aws-mgmt-cluster, you are currently logged in to my-vsphere-mgmt-cluster:

$ tanzu login
? Select a server  [Use arrows to move, type to filter]
> my-vsphere-mgmt-cluster  ()
  my-aws-mgmt-cluster      ()
  + new server

See Management Cluster Details

To see the details of a management cluster:

Run tanzu login to log in to the management cluster, as described in List Management Clusters and Change Context.

Run tanzu mc get. For example:

$ tanzu mc get
NAME         NAMESPACE   STATUS   CONTROLPLANE  WORKERS  KUBERNETES        ROLES
mc-test-cli  tkg-system  running  1/1           1/1      v1.22.9+vmware.1  management

Details:

NAME                                                            READY  SEVERITY  REASON  SINCE  MESSAGE
/mc-test-cli                                                    True                     29m
├─ClusterInfrastructure - AzureCluster/mc-test-cli              True                     30m
├─ControlPlane - KubeadmControlPlane/mc-test-cli-control-plane  True                     29m
│ └─Machine/mc-test-cli-control-plane-htlc4                     True                     30m
└─Workers
 └─MachineDeployment/mc-test-cli-md-0
   └─Machine/mc-test-cli-md-0-699df4dc76-9kgmw                 True                     30m

Providers:

 NAMESPACE                          NAME                   TYPE                    PROVIDERNAME  VERSION  WATCHNAMESPACE
 capi-kubeadm-bootstrap-system      bootstrap-kubeadm      BootstrapProvider       kubeadm       v0.3.14
 capi-kubeadm-control-plane-system  control-plane-kubeadm  ControlPlaneProvider    kubeadm       v0.3.14
 capi-system                        cluster-api            CoreProvider            cluster-api   v0.3.14
 capz-system                        infrastructure-azure   InfrastructureProvider  azure         v0.4.8

To see more options, run tanzu mc get --help. The Tanzu CLI alias mc is short for management-cluster.

Management Clusters, `kubectl`, and `kubeconfig`

Tanzu Kubernetes Grid does not automatically change the kubectl context when you run tanzu login to change the tanzu CLI context. Also, Tanzu Kubernetes Grid does not set the kubectl context to a workload cluster when you create it. To change the kubectl context, use the kubectl config use-context command.

By default, Tanzu Kubernetes Grid saves cluster context information in the following files on your bootstrap machine:

Management cluster contexts: ~/.kube-tkg/config
Workload cluster contexts: ~/.kube/config

Management Clusters and Their Configuration Files

When you run tanzu config init for the first time, it creates the ~/.config/tanzu/tkg subfolder that contains the Tanzu Kubernetes Grid configuration files. To deploy your first management cluster, you must specify the --ui or --file option with tanzu mc create:

tanzu mc create --ui creates a management cluster with the installer interface and saves the settings from your installer input into a cluster configuration file ~/.config/tanzu/tkg/clusterconfigs/UNIQUE-ID.yaml, where UNIQUE-ID is a generated filename.
tanzu mc create --file creates a management cluster using an existing cluster configuration file. The --file option applies to cluster configuration files only and does not change where the tanzu CLI references other files under ~/.config/tanzu/tkg.
tanzu mc create with neither the --ui nor --file option creates a management cluster using the default cluster configuration file ~/.config/tanzu/tkg/cluster-config.yaml.

If you are creating the management cluster on Tanzu Kubernetes Grid v1.5.0, v1.5.1, v1.5.2, or v1.5.3, you must run the tanzu plugin sync command after the management cluster is created successfully. This command installs the Tanzu Kubernetes Grid plugins.

The recommended practice is to use a dedicated configuration file for every management cluster that you deploy.

For more information about configuration files in Tanzu Kubernetes Grid, see What Happens When You Create a Management Cluster.

Add Existing Management Clusters to Your Tanzu CLI

The Tanzu CLI allows you to log in to a management cluster that someone else created. To log in, you can use the local kubeconfig details or the server endpoint option.

To log into an existing management cluster by using a local kubeconfig:

Run tanzu login, use your down-arrow key to highlight + new server, and press Enter.
```
tanzu login
? Select a server + new server
```

When prompted, select Local kubeconfig as your login type and enter the path to your local kubeconfig file, context, and the name of your server. For example:

tanzu login
? Select a server + new server
? Select login type Local kubeconfig
? Enter path to kubeconfig (if any) /Users/exampleuser/examples/kubeconfig
? Enter kube context to use new-mgmt-cluster-admin@new-mgmt-cluster
? Give the server a name new-mgmt-cluster
✔  successfully logged in to management cluster using the kubeconfig new-mgmt-cluster

To log into an existing management cluster using the Server endpoint option:

Run tanzu login, use your down-arrow key to highlight + new server, and press Enter.
```
tanzu login
? Select a server + new server
```
When prompted, select Server endpoint as your login type.
In the Enter Server endpoint field, enter the Kubernetes API Server IP address of the management cluster.
In the Give the server a name field, enter a name for the server, and press Enter.
If identity management is enabled on the management cluster, in the Okta login page that opens in the default browser, enter your Okta credentials. You are logged in to the management cluster.
Verify that the following output is displayed on the Tanzu CLI:

successfully logged in to management cluster by using the kubeconfig <server name>

Alternatively, you can run tanzu login with the --server, --kubeconfig, and --context options and bypass the interactive prompts.

Delete Management Clusters from Your Tanzu CLI Configuration

It is possible that you might add a management cluster that someone else created to your instance of the Tanzu CLI, that at some point you no longer require. Similarly, if you deployed a management cluster and that management cluster has been deleted from your infrastructure provider by means other than by running tanzu mc delete, that management cluster will continue to appear in the list of management clusters that the CLI tracks when you run tanzu login. In these cases, you can remove the management cluster from the list of management clusters that the Tanzu CLI tracks.

Run tanzu config server list, to see the list of management clusters that the Tanzu CLI tracks.
```
tanzu config server list
```
You should see all of the management clusters that you have either deployed yourself or added to the Tanzu CLI, the location of their kubeconfig files, and their contexts.
Run the tanzu config server delete command to remove a management cluster.
```
tanzu config server delete my-vsphere-mc
```

Running the tanzu config server delete command removes the cluster details from the ~/.config/tanzu/config.yaml and ~/.kube-tkg/config.yaml files. It does not delete the management cluster itself, if it still exists. To delete a management cluster rather than just remove it from the Tanzu CLI configuration, see Delete Management Clusters.

Scale Management Clusters

After you deploy a management cluster, you can scale it up or down by increasing or reducing the number of node VMs that it contains. To scale a management cluster, use the tanzu cluster scale command with one or both of the following options:

--controlplane-machine-count changes the number of management cluster control plane nodes.
--worker-machine-count changes the number of management cluster worker nodes.

Because management clusters run in the tkg-system namespace rather than the default namespace, you must also specify the --namespace option when you scale a management cluster.

Run tanzu login before you run tanzu cluster scale to make sure that the management cluster to scale is the current context of the Tanzu CLI.
To scale a production management cluster that you originally deployed with 3 control plane nodes and 5 worker nodes to 5 and 10 nodes respectively, run the following command:
```
tanzu cluster scale MANAGEMENT-CLUSTER-NAME --controlplane-machine-count 5 --worker-machine-count 10 --namespace tkg-system
```

If you initially deployed a development management cluster with one control plane node and you scale it up to 3 control plane nodes, Tanzu Kubernetes Grid automatically enables stacked HA on the control plane.

Important: Do not change context or edit the .kube-tkg/config file while Tanzu Kubernetes Grid operations are running.

Update Management Cluster Credentials (vSphere)

To update the vSphere credentials used by a management cluster, and optionally all of the workload clusters that it manages, see Update Management and Workload Cluster Credentials.

Manage Participation in CEIP

When you deploy a management cluster by using either the installer interface or the CLI, participation in the VMware Customer Experience Improvement Program (CEIP) is enabled by default, unless you specify the option to opt out. If you remain opted in to the program, the management cluster sends information about how you use Tanzu Kubernetes Grid back to VMware at regular intervals, so that we can make improvements in future versions.

For more information about the CEIP, see Manage Participation in CEIP.

If you opted out of the CEIP when you deployed a management cluster and want to opt in, or if you opted in and want to opt out, see Opt In or Out of the VMware CEIP in Manage Participation in CEIP to change your CEIP participation setting after deployment

Create Namespaces in the Management Cluster

To help you to organize and manage your development projects, you can optionally divide the management cluster into Kubernetes namespaces. You can then use Tanzu CLI to deploy Tanzu Kubernetes clusters to specific namespaces in your management cluster. For example, you might want to create different types of clusters in dedicated namespaces. If you do not create additional namespaces, Tanzu Kubernetes Grid creates all Tanzu Kubernetes clusters in the default namespace. For information about Kubernetes namespaces, see the Kubernetes documentation.

Make sure that kubectl is connected to the correct management cluster context by displaying the current context.
```
kubectl config current-context
```

List the namespaces that are currently present in the management cluster.

kubectl get namespaces

You will see that the management cluster already includes several namespaces for the different services that it provides:

capi-kubeadm-bootstrap-system       Active   4m7s
capi-kubeadm-control-plane-system   Active   4m5s
capi-system                         Active   4m11s
capi-webhook-system                 Active   4m13s
capv-system                         Active   3m59s
cert-manager                        Active   6m56s
default                             Active   7m11s
kube-node-lease                     Active   7m12s
kube-public                         Active   7m12s
kube-system                         Active   7m12s
tkg-system                          Active   3m57s

Use kubectl create -f to create new namespaces, for example for development and production.

These examples use the production and development namespaces from the Kubernetes documentation.
```
kubectl create -f https://k8s.io/examples/admin/namespace-dev.json
```
```
kubectl create -f https://k8s.io/examples/admin/namespace-prod.json
```

Run kubectl get namespaces --show-labels to see the new namespaces.

development                         Active   22m   name=development
production                          Active   22m   name=production

Delete Management Clusters

To delete a management cluster, run the tanzu mc delete command.

When you run tanzu mc delete, Tanzu Kubernetes Grid creates a temporary kind cleanup cluster on your bootstrap machine to manage the deletion process. The kind cluster is removed when the deletion process completes.

To see all your management clusters, run tanzu login as described in List Management Clusters and Change Context.
If there are management clusters that you no longer require, run tanzu mc delete.

You must be logged in to the management cluster that you want to delete.
```
tanzu mc delete my-aws-mgmt-cluster
```
To skip the yes/no verification step when you run tanzu mc delete, specify the --yes option.
```
tanzu mc delete my-aws-mgmt-cluster --yes
```
If there are Tanzu Kubernetes clusters running in the management cluster, the delete operation is not performed.

In this case, you can delete the management cluster in two ways:
- Run tanzu cluster delete to delete all of the running clusters and then run tanzu mc delete again.
- Run tanzu mc delete with the --force option.
```
tanzu mc delete my-aws-mgmt-cluster --force
```