Node registration configuration

Below is a list of node registration configuration options that can be set for kubeadm init and kubeadm join.

This customization will be available when the provider-specific cluster configuration patch is included in the ClusterClass.

Example

ignorePreflightErrors

Kubeadm runs preflight checks to ensure the machine is compatible with Kubernetes and its dependencies. The SystemVerification check is known to result in false positives. For example, it fails when the Linux Kernel version is not supported by kubeadm, even if the kernel has all the required features. For this reason, we skip the check by default.

Control plane

To configure ignorePreflightErrors for the control plane nodes, specify the following configuration:

apiVersion: cluster.x-k8s.io/v1beta1
kind: Cluster
metadata:
  name: <NAME>
spec:
  topology:
    variables:
      - name: clusterConfig
        value:
          controlPlane:
            nodeRegistration:
              ignorePreflightErrors:
                - SystemVerification

Applying this configuration will result in the following value being set:

• KubeadmControlPlaneTemplate:

  • spec:
      kubeadmConfigSpec:
        initConfiguration:
          nodeRegistration:
            nodeRegistration:
              ignorePreflightErrors:
                - SystemVerification
        joinConfiguration:
            nodeRegistration:
              ignorePreflightErrors:
                - SystemVerification
    

Worker node

ignorePreflightErrors for individual nodepools can be configured similarly:

apiVersion: cluster.x-k8s.io/v1beta1
kind: Cluster
metadata:
  name: <NAME>
spec:
  topology:
    workers:
      machineDeployments:
      - class: default-worker
        name: md-0
        variables:
          overrides:
          - name: workerConfig
            value:
              nodeRegistration:
                ignorePreflightErrors:
                  - SystemVerification

Applying this configuration will result in the following value being set:

• KubeadmConfigTemplate:

  • spec:
      joinConfiguration:
        nodeRegistration:
          ignorePreflightErrors:
            - SystemVerification
    

By default, the following value will be set for both control plane and worker nodes:

    variables:
      - name: clusterConfig
        value:
          controlPlane:
            nodeRegistration:
              ignorePreflightErrors:
                - SystemVerification
      - name: workerConfig
        value:
          nodeRegistration:
            ignorePreflightErrors:
              - SystemVerification

This can be enabled by setting ignorePreflightErrors to an empty list:

    variables:
      - name: clusterConfig
        value:
          controlPlane:
            nodeRegistration:
              ignorePreflightErrors: []
      - name: workerConfig
        value:
          nodeRegistration:
            ignorePreflightErrors: []