keepalived最初专为LVS设计用来监控LVS集群系统中各个节点的状态，后来加入VRRP功能。因此也可以做nginx，haproxy，mysql的高可用。

VRRP：虚拟路由器冗余协议，解决静态路由单点故障。 通过竞选协议来实现虚拟路由器的功能，所有的协议报文通过ip多播（多播地址224.0.0.18），虚拟路由器的vrid对外的MAC地址 00-00-5e-00-01-vrid.master会一直发VRRP广告包，如果BACKUP收不到广播包，会自己配置vip起服务。

############################################################# 安装keepalived yum install keepalived -y

vim /etc/keepalived/keepalived.conf ! Configuration File for keepalived global_defs { notification_email { lmkmike#qq.com } notification_email_from haproxy-ha@qq.com smtp_server 192.168.200.1 smtp_connect_timeout 30 router_id LV-master #每一台keepalived不一样

}

vrrp_instance VI_1 { state MASTER #角色 另外改BACKUP interface eth0 #网卡 virtual_router_id 51 #不能重复 priority 150 #权重 另外改100 advert_int 1 #检查时间默认1s authentication { auth_type PASS auth_pass haproxy_ha } virtual_ipaddress { 192.168.56.10/24 }

}

vrrp_instance VI_2 { state BACKUP #角色 另外改MASTER interface eth0 #网卡 virtual_router_id 60 #不能重复 priority 150 #权重 另外改100 advert_int 1 #检查时间默认1s authentication { auth_type PASS auth_pass haproxy_ha } virtual_ipaddress { 192.168.56.11/24 } }

virtual_server 192.168.56.10 80 { delay_loop 6 lb_algo wrr lb_kind DR nat_mask 255.255.255.0 persistence_timeout 300 protocol TCP

real_server 192.168.56.100 80 {
    weight 1
    TCP_CHECK {
        connect_timeout 3
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
    }
}
    real_server 192.168.56.21 80 {
    weight 1
    TCP_CHECK {
        connect_timeout 3
        nb_get_retry 3
        delay_before_retry 3
        connect_port 80
    }
}
}

############################################################# RS要配置VIP和抑制ARP 其他节点绑定vip ifconfig lo:0 192.168.56.10/32 up 抑制ARP echo 1 >/proc/sys/net/ipv4/conf/lo/arp_ignore echo 2 >/proc/sys/net/ipv4/conf/lo/arp_announce echo 1 >/proc/sys/net/ipv4/conf/all/arp_ignore echo 2 >/proc/sys/net/ipv4/conf/all/arp_announce ############################################################# 启动keepalived service keepalived start

查看lvs当前链接的状态 ipvsadm -lnc

上线RS时通过修改keepalived.cnf后优雅重启/etc/init.d/keepalived reload