Keepalived 之 双主模式+DNS轮询机制 实现高负载

一、Keepalived双主模式+DNS轮询机制作用

作用：在单主模式下，备机通常会以等待状态放着，不接受任何数据，导致所有数据请求只往主机-负载均衡发送，做成资源浪费；而双主模式，即创造两个VIP，两个VIP分别放在两台负载均衡的机器上，同时两台主机均为对方的备机，以作VIP的漂移，服务接管作用，加入DNS轮询机制，使客户端的域名分别依次解释到两个VIP上，形成两台负载均衡主机同时对外提供服务。同时也解决了单主模式下的单机性能屏颈。

二、网络拓扑图

三、两台负载均衡主机的Keepalived 配置文件

lb01 keepalived.conf

! Configuration File for keepalived

global_defs {
   notification_email {
   [email protected]
}
   notification_email_from [email protected]
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id lb01
}

vrrp_instance VI_1 {
    state MASTER
    interface eth1
    virtual_router_id 53
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 3333
    }
    virtual_ipaddress {
        10.3.150.200/24 dev eth1 label eth1:1
    }
}
vrrp_instance VI_2 {
    state BACKUP
    interface eth1
    virtual_router_id 54
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 4444
    }
    virtual_ipaddress {
        10.3.150.201/24 dev eth1 label eth1:1
    }
}

lb02 keepalived.conf

! Configuration File for keepalived

global_defs {
   notification_email {
   [email protected]
}
   notification_email_from [email protected]
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id lb01
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth1
    virtual_router_id 53
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 3333
    }
    virtual_ipaddress {
        10.3.150.200/24 dev eth1 label eth1:1
    }
}
vrrp_instance VI_2 {
    state MASTER
    interface eth1
    virtual_router_id 54
    priority 150
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 4444
    }
    virtual_ipaddress {
        10.3.150.201/24 dev eth1 label eth1:1
    }
}