前期搭建的是简易的单ETCD集群，目前需要升级为高可用的集群。采用keepalived+haproxy实现：

一、Docker新增加ECED的2个节点，其中之一节点的docker-compose文件如下，多个节点对应修改即可,注意以下标红的地方，否则会报错或新旧集群冲突问题：

version: '2'

services:
  Etcd:
    image: bitnami/etcd:3.5.13-debian-12-r9
    container_name: etcd3.5
    environment:
      - TZ=Asia/Shanghai
      - ALLOW_NONE_AUTHENTICATION=yes
      - ETCD_NAME=etcd2
      - ETCD_ADVERTISE_CLIENT_URLS=http://10.0.xx.20:2379  #告知集群自己的客户端地址
      - ETCD_LISTEN_CLIENT_URLS=http://0.0.0.0:2379 #设置监听客户端通讯的URL列表
      - ETCD_INITIAL_ADVERTISE_PEER_URLS=http://10.0.xx.20:2380 #告知集群自己集群通讯地址
      - ETCD_LISTEN_PEER_URLS=http://0.0.0.0:2380 #用于监听伙伴通讯的URL列表
      - ETCD_INITIAL_CLUSTER_TOKEN=etcd-cluster #etcd 集群的初始化集群记号
      - ETCD_INITIAL_CLUSTER=etcd2=http://10.0.xx.21:2380,etcd1=http://10.0.xx.20:2380,etcd3=http://10.0.xx.22:2380 #集群成员
      - ETCD_ACTIVE_ENDPOINTS=10.0.xx.21:2380,10.0.xx.20:2380,10.0.xx.22:2380
 #注意以上只需要写已经活动的节点，新加入第一个节点第一次只会有一个，后续数据同步完成可以都加上     
      - ETCD_INITIAL_CLUSTER_STATE=existing#第一个有数据的旧节点是new

      - ETCD_ELECTION_TIMEOUT=10000
    ports:
      - 2379:2379
      - 2380:2380
    volumes:
      - /xxxxxxxx/etcd/config/etcd.conf.yml:/opt/bitnami/etcd/conf/etcd.conf.yml
      - /xxxxxxxxx/etcd/data:/bitnami/etcd/data

二、安装haproxy负载均衡：

在乌邦图操作系统安装如下：

1)安装
sudo apt install software-properties-common
#安装最新指定版本，不安装默认版本
sudo add-apt-repository ppa:vbernat/haproxy-2.6 -y
sudo apt install haproxy -y
2)备份配置文件
mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.bak
3)编辑配置文件
vim /etc/haproxy/haproxy.cfg
#---------------------------------------------------------------------
# Example configuration for a possible web application.  See the
# full configuration options online.
#
#   https://www.haproxy.org/download/2.1/doc/configuration.txt
#   https://cbonte.github.io/haproxy-dconv/2.1/configuration.html
#
#---------------------------------------------------------------------

#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    # to have these messages end up in /var/log/haproxy.log you will
    # need to:
    #
    # 1) configure syslog to accept network log events.  This is done
    #    by adding the '-r' option to the SYSLOGD_OPTIONS in
    #    /etc/sysconfig/syslog
    #
    # 2) configure local2 events to go to the /var/log/haproxy.log
    #   file. A line like the following can be added to
    #   /etc/sysconfig/syslog
    #
    #    local2.*                       /var/log/haproxy.log
    #
    log         127.0.0.1 local2

#    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
#    user        haproxy
#    group       haproxy
    # daemon

    # turn on stats unix socket
    stats socket /var/lib/haproxy/stats

#---------------------------------------------------------------------
# common defaults that all the 'listen' and 'backend' sections will
# use if not designated in their block
#---------------------------------------------------------------------
defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000

#---------------------------------------------------------------------
# main frontend which proxys to the backends
#---------------------------------------------------------------------
frontend  etcd-server
    mode tcp
    bind *:12379  ## 监听2379端口
    # bind *:443 ssl # To be completed ....

    acl url_static       path_beg       -i /static /images /javascript /stylesheets
    acl url_static       path_end       -i .jpg .gif .png .css .js

    default_backend            etcd-server

#---------------------------------------------------------------------
# round robin balancing between the various backends
#---------------------------------------------------------------------
backend etcd-server
    mode        tcp  # 模式tcp
    balance     roundrobin  # 采用轮询的负载算法
# etcd-server backend  # 配置etcd，端口2379
 server etcd2 10.0.xx.20:2379 check
 server etcd1 10.0.xx.21:2379 check
 server etcd3 10.0.xx.22:2379 check
4)重启服务并设置开机重启:
sudo systemctl restart haproxy
sudo systemctl enable haproxy
sudo systemctl status haproxy

三、安装keepalived，并形成vip给k8s集群调用

本次采用docker-compose方式安装，yaml文件如下：

version: '3'
services:
  keepalived:
    image: osixia/keepalived
    container_name: keepalived
    network_mode: "host"
    volumes:
      - /xxxxx/keepalived/keepalived.conf:/container/service/keepalived/assets/keepalived.conf
    cap_add:
      - NET_ADMIN
      - NET_BROADCAST
      - NET_RAW
    command: --copy-service

keepalived.conf文件如下：

global_defs {
   script_user root 
   enable_script_security

}

vrrp_script chk_haproxy {
    script "/bin/bash -c 'if [[ $(netstat -nlp | grep 12379) ]]; then exit 0; else exit 1; fi'"  # haproxy 检测
    interval 2  # 每2秒执行一次检测
    weight 11 # 权重变化
}

vrrp_instance VI_1 {
  interface ens160 #绑定节点网卡，不能出错

  state MASTER # backup节点设为BACKUP
  virtual_router_id 51 # id设为相同，表示是同一个虚拟路由组
  priority 100 #初始权重
nopreempt #可抢占

  unicast_peer {

  }

  virtual_ipaddress {
    10.0.xx.27  # vip
  }

  authentication {
    auth_type PASS
    auth_pass password
  }

  track_script {
      chk_haproxy
  }

  notify "/container/service/keepalived/assets/notify.sh"
}

各节点分别使用docker部署一个容器运行，配置文件根据需要微调。部署完成以后则原来的单节点ETCD升级为高可用集群。k8s管理节点只需要调用vip+端口即可。