keepalived 单主、非抢占、单播示例

keepalived 单主、非抢占、单播 示例

server	hostname	ip
keepalived	z6	192.168.1.106
keepalived	z7	192.168.1.107

一、单主设置

一共2台服务器：192.168.1.106 为 master 设置如下

root@z7:~# apt install  keepalived
root@z7:~# cp  /usr/share/doc/keepalived/samples/keepalived.conf.sample  /etc/keepalived/keepalived.conf
root@z7:~# systemctl restart keepalived
root@z7:~# scp /etc/keepalived/keepalived.conf  192.168.1.106:/etc/keepalived/

conf

vrrp_instance VI_1{
    state MASTER
    interface eth0
    virtual_router_id 50
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111qwer

    }
    virtual_ipaddress {
        192.168.7.248/24  dev eth0 label eth0:1
    }
}

192.168.1.105 为backup ， 设置如下

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111qwer

    }
    virtual_ipaddress {
        192.168.7.248/24  dev eth0 label eth0:1
    }
}

默认是抢占式，组播的 方式 。当master down 时，backup 会接管vip 地址。

抢占式的缺点：会因为网络抖动，vip频繁飘移， 造成不必要的切换。推荐使用非抢占式

组播的缺点： keepalived在组播模式下所有的信息都会向224.0.0.18的组播地址发送，产生众多的无用信息，并且会产生干扰和冲突，所以需要将其组播的模式改为单拨。这是一种安全的方法，避免局域网内有大量的keepalived造成虚拟路由id的冲突。单播模式需要关闭vrrp_strict，严格遵守vrrp协议这个选项

二、非抢占模式

nopreempt：定义工作模式为非抢占模式

state 为 backup

z6:

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

    }
    virtual_ipaddress {
        192.168.7.248/24  dev eth0 label eth0:1
    }

z7:

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 80
    advert_int 1
     nopreempt
    authentication {
        auth_type PASS
        auth_pass 1111qwer

    }

当停止z6的时候，ip 会飘移到z7的机器，当z6 重新启动的时候，不会漂回来，仍然在z7 的机器上

三、单播模式

格式

unicast_src_ip 本机源IP 
	unicast_peer{ 
	目标主机IP 
    }

z6:

vrrp_instance VI_1{
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 100
    advert_int 1
    nopreempt
    unicast_src_ip 192.168.1.106
    unicast_peer {
        192.168.1.107
    }
    authentication {
        auth_type PASS
        auth_pass 1111qwer

    }
    virtual_ipaddress {
        192.168.7.248/24  dev eth0 label eth0:1
    }
}

z7:

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    virtual_router_id 50
    priority 80
    advert_int 1
     nopreempt
    unicast_src_ip 192.168.1.107
    unicast_peer {
        192.168.1.106
    }

    authentication {
        auth_type PASS
        auth_pass 1111qwer

    }
    virtual_ipaddress {
        192.168.7.248/24  dev eth0 label eth0:1
    }

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