keepalived高可用

yum install -y keepalived

systemctl start keepalived.service      ---启动
systemctl  enable  keepalived.sercice   ---开机自启

[root@lb01 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
    
    global_defs {                       #全局配置
       notification_email {
         acassen@firewall.loc           #邮箱地址配置(主服务出现vip切换, 需要进行邮件告知管理员)
       }
       notification_email_from Alexandre.Cassen@firewall.loc
       smtp_server 192.168.200.1        #邮件信息配置
       smtp_connect_timeout 30
       router_id lb01                   #定义一个高可用集群中节点名称
    }
    
    vrrp_instance(家族) china {         #vrrp协议响应参数配置   数据库-实例  tomcat--实例
        state MASTER                    #指定服务器在高可用服务中的身份(MASTER BACKUP)
        interface eth0                  #指定vip地址出现在哪个网卡上
        virtual_router_id 66            #家族标识
        priority 150                    #设置服务器优先级, 优先级越高, 越有可能成为主
        advert_int 1                    #主服务器发送组播包间隔
        authentication {                #配置高可用服务认证信息
            auth_type PASS              #确认进行组播通讯主机是在一个实例中
            auth_pass 1234
        }
        virtual_ipaddress {
            10.0.0.3                    #定义vip地址信息
        }
    }

[root@lb02 ~]# vim /etc/keepalived/keepalived.conf 
! Configuration File for keepalived
    
    global_defs {                       #全局配置
       notification_email {
         acassen@firewall.loc           #邮箱地址配置(主服务出现vip切换, 需要进行邮件告知管理员)
       }
       notification_email_from Alexandre.Cassen@firewall.loc
       smtp_server 192.168.200.1        #邮件信息配置
       smtp_connect_timeout 30
       router_id lb02                   #定义一个高可用集群中节点名称   *主备不一样*
    }
    
    vrrp_instance(家族) china {         #vrrp协议响应参数配置   数据库-实例  tomcat--实例
        state BACKUP                    #指定服务器在高可用服务中的身份(MASTER BACKUP)
                                           # *主备不一样*
        interface eth0                  #指定vip地址出现在哪个网卡上
        virtual_router_id 66            #家族标识
        priority 100                    #设置服务器优先级, 优先级越高, 越有可能成为主
                                           # *主备不一样*
        advert_int 1                    #主服务器发送组播包间隔
        authentication {                #配置高可用服务认证信息
            auth_type PASS              #确认进行组播通讯主机是在一个实例中
            auth_pass 1234
        }
        virtual_ipaddress {
            10.0.0.3                    #定义vip地址信息
        }
    }

[root@lb02 scripts]# cat monitor_vip.sh 
#!/bin/bash
vip_info="10.0.0.3"
ip a s eth0|grep "$vip_info" >/dev/null
REVAL=$? 

if [ $REVAL -eq 0 ]
then
echo "pls check keepalived server" |mail -s "keepalived error" XXXX@qq.com
fi

[root@lb02 scripts]#  crontab -e 
* * * * *  /bin/sh /server/scripts/monitor_vip.sh &>/dev/null

方法一: 实现秒级执行监控脚本
 #!/bin/bash                         
       ps_num=$(ps -ef|grep -c n[g]inx)
       
       while true  
       do
          if [ $ps_num -lt 2 ]
          then
             systemctl stop keepalived
          fi
          sleep 2
       do    

[root@lb01 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
    router_id lb01
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 50
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
}
    virtual_ipaddress {
        10.0.0.3
    }
}

[root@lb02 ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {     
    router_id lb02   
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 100
    nopreempt
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
}
    virtual_ipaddress {
        10.0.0.3
    }
}