backup

[root@backup ~]# vim /etc/keepalived/keepalived.conf
[root@backup ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   router_id lb02    
}

vrrp_instance VI_1 {       //这里主备节点需要一致
    state BACKUP
    interface ens33      //网卡
    virtual_router_id 51
    priority 90     //这里比主节点的小
    advert_int 5
    authentication {
        auth_type PASS
        auth_pass tushanbu   //密码(可以随机生成)
    }
    virtual_ipaddress {
        192.168.222.133    //高可用虚拟IP（VIP）地址
    }
    notify_master "/scripts/notify.sh master 192.168.222.133"           //添加
    notify_backup "/scripts/notify.sh backup 192.168.222.133"           //添加
}

virtual_server 192.168.222.133 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.222.250 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }

    real_server 192.168.222.137 80 {
        weight 1
        TCP_CHECK {
            connect_port 80
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
        }
    }
}
[root@backup ~]# systemctl restart keepalived.service 

测试

模拟haproxy服务故障
master端

[root@master ~]# ip a   //有vip
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:05:f4:28 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.250/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet 192.168.222.133/32 scope global ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe05:f428/64 scope link 
       valid_lft forever preferred_lft forever
[root@master ~]# curl 192.168.222.133
RS1
[root@master ~]# curl 192.168.222.133
RS2
[root@master ~]# systemctl stop haproxy.service 
[root@master ~]# systemctl restart keepalived.service 
[root@master ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:05:f4:28 brd ff:ff:ff:ff:ff:ff
    inet 192.168.222.250/24 brd 192.168.222.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe05:f428/64 scope link 
       valid_lft forever preferred_lft forever

backup
backup变成主