kubernetes：驱逐node上所有pod

背景：
有时候我们要对一个node节点进行维修，升级，需要重启开关机，那怎么才能做到应用不影响呢？
技术：
我们可以使用 命令操作

封锁节点，先让节点变的不可调度

kubectl cordon <node name>

驱逐pod，该操作做完之后就可以进行节点升级等操作

kubectl drain <node name>

官方文档：
https://kubernetes.io/docs/tasks/administer-cluster/safely-drain-node/
https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands#drain

子命令

```bash
Options:
      --delete-local-data=false: Continue even if there are pods using emptyDir (local data that will be deleted when
the node is drained).
      --dry-run=false: If true, only print the object that would be sent, without sending it.
      --force=false: Continue even if there are pods not managed by a ReplicationController, ReplicaSet, Job, DaemonSet
or StatefulSet.
      --grace-period=-1: Period of time in seconds given to each pod to terminate gracefully. If negative, the default
value specified in the pod will be used.
      --ignore-daemonsets=false: Ignore DaemonSet-managed pods.
      --pod-selector='': Label selector to filter pods on the node
  -l, --selector='': Selector (label query) to filter on
      --timeout=0s: The length of time to wait before giving up, zero means infinite

Usage:
  kubectl drain NODE [options]

注意：如果执行过程中不需要驱逐 DS容器，使用–ignore-daemonsets=false
执行之后会有error报错 ，请忽略

解封锁

kubectl uncordon <node name>

之后正常使用

如果想移除某个节点

kubectl  delete  node  <node name>

重新加回的话 重启node节点，或者重启node上的 kubelet ，kube-proxy即可