现集群架构是单master（192.168.110.3），为了提升高可用性决定增加2个master(192.168.110.4、192.168.110.5)，但是当192.168.110.3宕机，需要逐个变更worker节点的/etc/kubernetes/kubelet.conf配置，所以决定安装kube-vip。

安装kube-vip Static Pods

根据官网文档分别在3台master上创建kube-vip

$vim /etc/kubernetes/manifests/kube-vip.yaml

apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  name: kube-vip
  namespace: kube-system
spec:
  containers:
  - args:
    - manager
    env:
    - name: vip_arp
      value: "true"
    - name: port
      value: "6443"
    - name: vip_interface
      value: ens192 #网卡
    - name: vip_cidr
      value: "32"
    - name: cp_enable
      value: "true"
    - name: cp_namespace
      value: kube-system
    - name: vip_ddns
      value: "false"
    - name: svc_enable
      value: "true"
    - name: vip_leaderelection
      value: "true"
    - name: vip_leaseduration
      value: "5"
    - name: vip_renewdeadline
      value: "3"
    - name: vip_retryperiod
      value: "1"
    - name: address
      value: 192.168.110.220 #vip
    image: ghcr.io/kube-vip/kube-vip:v0.4.0
    imagePullPolicy: Always
    name: kube-vip
    resources: {}
    securityContext:
      capabilities:
        add:
        - NET_ADMIN
        - NET_RAW
        - SYS_TIME
    volumeMounts:
    - mountPath: /etc/kubernetes/admin.conf
      name: kubeconfig
  hostAliases:
  - hostnames:
    - kubernetes
    ip: 127.0.0.1
  hostNetwork: true
  volumes:
  - hostPath:
      path: /etc/kubernetes/admin.conf
    name: kubeconfig
status: {}

稍等之后，测试vip网络

$tcping 192.168.110.220 6443
192.168.110.220 port 6443 open.

变更controlPlaneEndpoint配置

$kubectl edit cm kubeadm-config -n kube-system

#编辑以下内容
···
     clusterName: kubernetes
     controlPlaneEndpoint: ${vip}:6443
···

master逐个更新apiserver证书

否则更改kubeconfig server后连接爆“Error while proxying request: tls: failed to verify certificate: x509”

#删除旧证书
$rm /etc/kubernetes/pki/apiserver.*
#更新证书
$kubeadm init phase certs apiserver --control-plane-endpoint 192.168.110.220:6443

worker节点逐个更新kubelet配置

否则一旦master宕机，无法正常工作

$sed -i 's/192.168.110.3/192.168.110.220/g' /etc/kubernetes/kubelet.conf
$systemctl restart kubelet