Validation permits having cloudProvider.none and machineController.deploy=true

[kron4eg]

What happened?

Sometimes people can be confused and try to set unsupported config combination that lead to very obscure error messages, for example in this case:

Task failed, error was: runtime: unmarshalling manifest "deployment-controller.yaml"
error converting YAML to JSON: yaml: line 64: could not find expected ':'

Expected behavior

KubeOne should error out early, clearly indicating that such a config is not supported.

What KubeOne version are you using?

Any of them.

Provide your KubeOneCluster manifest here (if applicable)

apiVersion: kubeone.k8c.io/v1beta2
kind: KubeOneCluster
name: kubeone
versions:
  kubernetes: 1.29.7

cloudProvider:
  none: {}

controlPlane:
  hosts:
    - privateAddress: 10.xxx
    - privateAddress: 10.xxx
    - privateAddress: 10.xxx

apiEndpoint:
  host: 10.xxx
  alternativeNames:
    - seed.xxx
  port: 6443

machineController:
  deploy: true
operatingSystemManager:
  deploy: true

[xmudrii]

KubeOne should error out early, clearly indicating that such a config is not supported.

This config should be supported, but we shouldn't deploy any credentials.

[kron4eg]

KubeOne should error out early, clearly indicating that such a config is not supported.

This config should be supported, but we shouldn't deploy any credentials.

How so? What's the purpose of credential-less and cloud-less machine-controller and osm?

[xmudrii]

@kron4eg machine-controller has more providers than what we support in KubeOne. The most notable example is Kubevirt, I could create a KubeOne cluster, deploy machine-controller and OSM, deploy credentials, and then use the machine-controller to create Kubevirt-based nodes.

[kron4eg]

In that case we should start supporting kubevirt. But until we not, this is an invalid configuration from K1 PoV.