Configuring DataStax Mission Control

DataStax Mission Control is current in Private Preview. It is subject to the beta agreement executed between you and DataStax. DataStax Mission Control is not intended for production use, has not been certified for production workloads, and might contain bugs and other functional issues. There is no guarantee that DataStax Mission Control will ever become generally available. DataStax Mission Control is provided on an “AS IS” basis, without warranty or indemnity of any kind.

If you are interested in trying out DataStax Mission Control please contact your DataStax account team.

As lifecycle changes occur and clusters and datacenters are created and terminated, adjust the Data Plane installation accordingly. Whenever a cluster is installed in Data Plane Mode, it needs to be configured to communicate with an independent cluster installed as the Control Plane.

Prerequisites

Download the create-clientconfig.sh script that contains:
1. kubectl
2. yq

Example

There are three (3) Kubernetes clusters named control, east, and west. In this procedure configure the Control Plane cluster so that it has access to the east and west clusters.

Assumptions

The user can access all 3 clusters with kubectl.
The default kubeconfig located at ~/.kube/config provides access to all 3 clusters.
DataStax Mission Control is installed in each of the 3 clusters in the mission-control namespace.

Procedure

Configure access for the east cluster by running the following script:
```
create-clientconfig.sh --namespace mission-control --src-context east  --dest-context control --output-dir east-clientconfig
```
1. Description of the options follows:
  
  --namespace specifies the namespace in which the ClientConfig and kubeconfig secret should be created.
  
  --src-context specifies the Data Plane cluster. It is the source cluster from which to obtain credentials that get stored in a secret and referenced by the generated ClientConfig.
  
  --dest-context specifies the Control Plane cluster. It is the cluster into which the kubeconfig secret and ClientConfig should be created.
  
  --output-dir specifies the directory in which to store generated manifests for the kubeconfig secret and ClientConfig. If not specified a temp directory is used.
Sample output:
```
Creating clientconfigs/kubeconfig
Creating secret east-config
Error from server (NotFound): secrets "east-config" not found
secret/east-config created
Creating ClientConfig clientconfigs/east.yaml
clientconfig.config.k8ssandra.io/east created
```
The error message can be ignored.

The east-clientconfig directory contains two files - east.yaml and kubeconfig.

kubeconfig is a kubeconfig file whose contents vary based on the Kubernetes distribution or cloud provider that you are using.

east.yaml should look like this:
```
apiVersion: config.k8ssandra.io/v1beta1
kind: ClientConfig
metadata:
  name: east
spec:
  contextName: east
  kubeConfigSecret:
    name: east-config
```
In the Control Plane cluster look for a kind: ClientConfig named east and a secret named east-config in the mission-control namespace.
Repeat step 1 for the west cluster.