GKE and EKS rely on exec based auth in the kubeconfig to authenticate with the k8s API server. This is currently not supported on SkyPilot controllers.

For example, say the user has two GKE clusters using exec based auth, GKE1 and GKE2:

• If the controller is launched on GKE1, the controller will be able to launch clusters on GKE1, but not on GKE2.
• If the controller is launched on any other cloud, the controller will not be able to launch clusters on GKE1 OR GKE2.

Here's the reason why we don't support exec based auth:

The current suggested workaround is to create a kubeconfig that uses token based auth with a service account (generate_kubeconfig.sh).

This workaround introduces friction for users, and may not be be feasible in environments where users cannot create service accounts.

We should support exec based auth, maybe starting with supporting GKE and EKS. This would require installing relevant dependencies and copying over the cloud credentials.