Cluster API - Bootstrap provider

k0smotron can act as a Cluster API Boostrap provider. As k0smotron itself will run the cluster control plane within the management cluster the bootstrap provider is (currently) focusing only on bootstrapping worker nodes.

As with any other Cluster API provider you must create a Machine object with a reference to a bootstrap provider:

apiVersion: cluster.x-k8s.io/v1beta1
kind: Machine
metadata:
  name: cp-test-0
spec:
  clusterName: cp-test
  bootstrap:
    configRef: # This triggers our controller to create cloud-init secret
      apiVersion: bootstrap.cluster.x-k8s.io/v1beta1
      kind: K0sWorkerConfig
      name: cp-test-0
  infrastructureRef:
    apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
    kind: HCloudMachine
    name: cp-test-0

Next we need to provide the configuration for the bootstrapping:

apiVersion: bootstrap.cluster.x-k8s.io/v1beta1
kind: K0sWorkerConfig
metadata:
  name: cp-test-0
spec:

As k0s comes with all the needed bells and whistles to get k8s worker node up, we do not need to specify any details in this simple example.

Check the examples pages for more detailed examples how k0smotron can be used with various Cluster API infrastructure providers.

For reference on what can be configured via K0sWorkerConfig see the reference docs.