一、keepalive介绍

1.1 keepalived介绍

keepalived介绍

1.2 nginx+keepalived架构图

image.png

二、配置nginx+keepalived

2.1 安装nginx

安装Nginx

2.2 安装keepalived

keepalived安装

2.3 配置keepalived

2.3.1 nginx01(192.168.10.3)keepalived配置

  1. /etc/keepalived/keepalived.conf
  3. ! Configuration File for keepalived
  5. global_defs {
  6.    router_id LVS_01               # router_if LVS_02
  7. }
  9. vrrp_instance VI_1 {
  10.     state MASTER                  # BACKUP
  11.     interface eth33                                # 通信端口 通过ip addr可以看到 根据自己的机器配置
  12.     virtual_router_id 51                    # vrrp实例id  keepalived集群，实例id必须一致
  13.     priority 100                      # 从：99
  14.     advert_int 1
  15.     authentication {
  16.         auth_type PASS
  17.         auth_pass 1111
  18.     }
  19.     virtual_ipaddress {                        # 自定义虚拟IP 
  20.             192.168.10.111
  21.     }
  22. }

2.3.2 nginx02(192.168.10.4)keepalived配置

/etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_02
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth33
    virtual_router_id 51
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
            192.168.10.111
    }
}

2.3.3 nginx01,02添加检测脚本

1) 创建脚本 vim /usr/local/src/nginx_check.sh

#!/bin/bash
A=`ps -C nginx --no-header |wc -l`                                           #统计nginx进程是否存在
if [ $A -eq 0 ];then                                                #为0，表明nginx停止了
      /usr/local/nginx/sbin/nginx                                    #尝试重启nginx
      if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then  #nginx重启失败，则keepalived自杀，进行VIP转移
              killall keepalived                                                #杀掉，vip就漫游到另一台机器                
      fi
fi

2) 修改keepalived配置,添加脚本 vim /etc/keepalived/keepalived.conf

vrrp_script nginx_check{
        script "/usr/local/src/nginx_check.sh"
      interval 2    #检测脚本执行间隔时间  单位秒
}
track_script{
        nginx_check    #调用检测脚本
}

三、启动nginx和keepalived

systemctl start nginx
systemcat start keepalived