手动搭建Kubernetes集群，部署keepalived+haproxy 高可用（第二章）

在第一章中，我们完成了集群的基础规划，并成功部署了Etcd数据库集群。

角色	IP	主机名	组件
Master01	192.168.22.10	k8s-master01	kube-apiserver，kube-scheduler，kube-controller-manager，containerd，keepalived，haproxy
Master02	192.168.22.11	k8s-master02	kube-apiserver，kube-scheduler，kube-controller-manager，containerd，etcd，keepalived，haproxy
Node01	192.168.22.12	k8s-node01	kubelet，kube-proxy，containerd，etcd
Node02	192.168.22.13	k8s-node02	kubelet，kube-proxy，containerd，etcd

部署在两台master节点

yum安装 keepalived 和 haproxy

yum -y install keepalived haproxy

修改haproxy配置

mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg-bak
vim /etc/haproxy/haproxy.cfg
global
  maxconn  2000
  ulimit-n  16384
  log  127.0.0.1 local0 warning
  stats timeout 30s

defaults
  log global
  mode  http
  option  httplog
  timeout connect 5s           
  timeout client  30s          
  timeout server  30s          
  timeout http-request 5s      
  timeout http-keep-alive 30s  

frontend monitor-in
  bind *:33305
  mode http
  option httplog
  monitor-uri /monitor

frontend k8s-master
  bind 0.0.0.0:16443
  bind 127.0.0.1:16443
  mode tcp
  option tcplog
  tcp-request inspect-delay 5s
  default_backend k8s-master

backend k8s-master
  mode tcp
  option tcplog
  option tcp-check
  balance roundrobin            
  default-server inter 10s downinter 5s rise 2 fall 2 slowstart 60s maxconn 250 maxqueue 256 weight 100
  server k8s-master01 192.168.22.10:6443 check port 6443 inter 2000 rise 2 fall 3  
  server k8s-master02 192.168.22.11:6443 check port 6443 inter 2000 rise 2 fall 3

k8s-master01配置keepalived

mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf-bak
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id k8s-master01
   script_user root
}

vrrp_script chkapiserver {
   script "/etc/keepalived/checkapiserver.sh"
   interval 5
   weight -5
   fall 2
   rise 1
}

vrrp_instance xx1 {
   state MASTER
   interface ens33
   mcast_src_ip 192.168.22.10
   virtual_router_id 51
   priority 100
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHAKAAUTH
   }
   virtual_ipaddress {
       192.168.22.222
   }
   track_script {
       chkapiserver
   }
}

k8s-master02配置keepalived

mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf-bak
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id k8s-master02
   script_user root
}

vrrp_script chkapiserver {
   script "/etc/keepalived/checkapiserver.sh"
   interval 5
   weight -5
   fall 2
   rise 1
}

vrrp_instance xx2 {
   state BACKUP
   interface ens33
   mcast_src_ip 192.168.22.11
   virtual_router_id 51
   priority 80
   advert_int 2
   authentication {
       auth_type PASS
       auth_pass K8SHAKAAUTH
   }
   virtual_ipaddress {
       192.168.22.222
   }
   track_script {
       chkapiserver
   }
}

健康检测脚本，所有主节点都需要

vim /etc/keepalived/checkapiserver.sh
#!/bin/bash

# 定义一个计数器，用于记录检测失败的次数
fail_count=0

# 循环检查 3 次
for i in {1..3}; do
  # 使用 pgrep 检查 haproxy 进程是否存在
  if ! pgrep -x haproxy > /dev/null; then
    # 如果没有找到 haproxy 进程，增加失败计数
    fail_count=$((fail_count+1))
    # 等待 1 秒后重试
    sleep 1
  else
    # 如果找到了 haproxy 进程，退出循环
    fail_count=0
    break
  fi
done

# 如果失败计数大于 0，说明haproxy服务可能停止了
if [ $fail_count -gt 0 ]; then
  # 打印停止 Keepalived 的信息
  echo "haproxy is not running, stopping keepalived"
  # 停止 Keepalived 服务
  systemctl stop keepalived
  # 脚本退出，返回错误状态码 1
  exit 1
fi

# 如果一切正常，脚本退出，返回成功状态码 0
exit 0        //保存退出
chmod +x /etc/keepalived/checkapiserver.sh

启动 keepalived 与 haproxy

systemctl daemon-reload
systemctl enable --now haproxy.service
systemctl enable --now keepalived.service

k8s-master1主节点查看IP

验证关闭k8s-master01节点

systemctl stop keepalived.service

k8s-master02节点查看IP

启动k8s-master01节点

第三章配置Master管理监控节点和Node工作节点的核心组件