feat(ntp): Configure NTP for clusters

[thunderboltsid]

• Add API for configuring NTP servers
• Add mutation handlers for injecting NTP servers

How has this been tested?

• Create a cluster with custom NTP configuration

apiVersion: cluster.x-k8s.io/v1beta1
kind: Cluster
metadata:
  annotations:
    caren.nutanix.com/cluster-uuid: 0197a351-97fa-7b0c-88a7-aa83fb309884
  labels:
    cluster.x-k8s.io/provider: nutanix
    konvoy.d2iq.io/cluster-name: nkp-sid
    konvoy.d2iq.io/provider: nutanix
  name: nkp-sid
  namespace: default
spec:
  clusterNetwork:
    pods:
      cidrBlocks:
      - 192.168.0.0/16
    services:
      cidrBlocks:
      - 10.96.0.0/12
  controlPlaneEndpoint:
    host: ""
    port: 0
  topology:
    class: nutanix-quick-start
    controlPlane:
      metadata: {}
      replicas: 3
    variables:
    - name: clusterConfig
      value:
        ...
        ntp:
          servers:
          - time.google.com

• Observe the kubeadmconfigs for machines have NTP Server set correctly

$ k get kubeadmconfigs -o yaml | grep ntp -A 3
    ntp:
      enabled: true
      servers:
      - time.google.com
--
    ntp:
      enabled: true
      servers:
      - time.google.com
--
    ntp:
      enabled: true
      servers:
      - time.google.com
--
    ntp:
      enabled: true
      servers:
      - time.google.com
--
    ntp:
      enabled: true
      servers:
      - time.google.com

• Update the ntp config to point to a different NTP server and observe a machine rollout with new kubeadmconfigs set to the new NTP server

$ k get kubeadmconfigs -o yaml | grep ntp -A 3
    ntp:
      enabled: true
      servers:
      - time.aws.com
--
    ntp:
      enabled: true
      servers:
      - time.aws.com
--
    ntp:
      enabled: true
      servers:
      - time.aws.com
--
    ntp:
      enabled: true
      servers:
      - time.aws.com
--
    ntp:
      enabled: true
      servers:
      - time.aws.com

[dkoshkin]

Thanks for this!

[dlipovetsky]

Thank you!