K8s delete the node when I shutdown the vm?

[shenxg13]

What happened:
k8s delete the node when I shutdown the vm and rejoin the node when vm restart, but the node label no longer there.

What you expected to happen:

How to reproduce it (as minimally and precisely as possible):

Anything else we need to know?:
[root@k8s-192-168-0-52-kube01 mongodb]# kubectl get node --show-labels
NAME STATUS ROLES AGE VERSION LABELS
k8s-192-168-0-52-kube01 Ready 21h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-52-kube01,level=1
k8s-192-168-0-53-kube02 Ready 24m v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-53-kube02,level=2
k8s-192-168-0-54-kube03 Ready 21h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-54-kube03,level=2

After I shutdown node k8s-192-168-0-53-kube02:
[root@k8s-192-168-0-52-kube01 mongodb]# kubectl get node --show-labels
NAME STATUS ROLES AGE VERSION LABELS
k8s-192-168-0-52-kube01 Ready 22h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-52-kube01,level=1
k8s-192-168-0-54-kube03 Ready 21h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-54-kube03,level=2

After I restart that node, the node rejoin the cluster but the label level=2 no longer there.
[root@k8s-192-168-0-52-kube01 mongodb]# kubectl get node --show-labels
NAME STATUS ROLES AGE VERSION LABELS
k8s-192-168-0-52-kube01 Ready 22h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-52-kube01,level=1
k8s-192-168-0-53-kube02 NotReady 1s v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-53-kube02
k8s-192-168-0-54-kube03 Ready 21h v1.8.7 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,kubernetes.io/hostname=k8s-192-168-0-54-kube03,level=2

Environment:

• Kubernetes version (use kubectl version):
  Client Version: version.Info{Major:"1", Minor:"8", GitVersion:"v1.8.7", GitCommit:"b30876a5539f09684ff9fde266fda10b37738c9c", GitTreeState:"clean", BuildDate:"2018-01-16T21:59:57Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"linux/amd64"}
  Server Version: version.Info{Major:"1", Minor:"8", GitVersion:"v1.8.7", GitCommit:"b30876a5539f09684ff9fde266fda10b37738c9c", GitTreeState:"clean", BuildDate:"2018-01-16T21:52:38Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"linux/amd64"}

• Cloud provider or hardware configuration:
  vSphere 6.5

• OS (e.g. from /etc/os-release):
  CentOS Linux release 7.4.1708 (Core)

• Kernel (e.g. uname -a):

• Install tools:

• Others:

[embano1]

Just to clarify, the node has to rejoin the cluster, i.e. the node object in K8s API is deleted and a new one is created in your case?

Just rebooting a worker VM should not cause this behaviour.