• Keepalived: настройка высокой доступности и плавающих IP адресов в CentOS 7
• Отказоустойчивый кластер с балансировкой нагрузки с помощью keepalived

nodeN# apt install keepalived

node1# cat /etc/keepalived/keepalived.conf

vrrp_instance VI_1 {
    state MASTER
    interface eth0
#    interface br0
    virtual_router_id 1
    virtual_ipaddress {
        192.168.X.254 label eth0:1
#        192.168.X.254 label br0:1
        172.16.1.X/24 dev eth1
        172.16.2.X/24 dev eth3
    }
    notify_backup "/usr/local/bin/vrrp.sh BACKUP"
    notify_master "/usr/local/bin/vrrp.sh MASTER"
}

node2# cat /etc/keepalived/keepalived.conf

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
#    interface br0
    virtual_router_id 1
    virtual_ipaddress {
        192.168.X.254 label eth0:1
#        192.168.X.254 label br0:1
        172.16.1.X/24 dev eth1
        172.16.2.X/24 dev eth3
    }
    notify_backup "/usr/local/bin/vrrp.sh BACKUP"
    notify_master "/usr/local/bin/vrrp.sh MASTER"
}

nodeN# cat /usr/local/bin/vrrp.sh

#!/bin/sh

#echo $1 >> /tmp/vrrp.txt

case $1 in
    MASTER)
        ip route delete default
        ip route add default via 172.16.1.254 table 101
        ip route add default via 172.16.2.254 table 102
        /root/select_isp.sh
    ;;
    BACKUP)
        ip route add default via 192.168.X.254
    ;;
esac

nodeN# chmod +x /usr/local/bin/vrrp.sh

nodeN# service keepalived restart