​ master/slave的单主架构，同一时间只有一个Keepalived对外提供服务，此主机繁忙，而另一台主机却很空闲，利用率低下，可以使用master/master的双主架构，解决此问题。

master/master的双主架构：

​ 即将两个或以上VIP分别运行在不同的keepalived服务器，以实现服务器并行提供web访问的目的，提高服务器资源利用率

ha1主机配置

[root@ka1-centos8 ~]# vim /etc/keepalived/keepalived.conf        
! Configuration File for keepalived
global_defs {
    notification_email {
        [email protected]
    }
    notification_email_from keepalived@localhost
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id ka1.magedu.org
    vrrp_mcast_group4 224.0.100.100
}

vrrp_instance VI_1 {
    state MASTER            # 在另一个主机上为BACKUP
    interface eth0
    virtual_router_id 66    # 每个vrrp_instance唯一
    priority 100            # 在另一个主机上为80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 12345678
    }
    virtual_ipaddress {
        10.0.0.10/24 dev eth0 label eth0:1 #指定vrrp_instance各自的VIP
    }
}

vrrp_instance VI_2 {            # 添加 VI_2 实例
    state BACKUP                # 在另一个主机上为MASTER
    interface eth0
    virtual_router_id 88        # 每个vrrp_instance唯一
    priority 80                 # 在另一个主机上为100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 12345678
    }
    virtual_ipaddress {
        10.0.0.20/24 dev eth0 label eth0:1  # 指定vrrp_instance各自的VIP
    }
}

ka2主机配置,和ka1配置只需五行不同

[root@ka2-centos8 ~]#vim /etc/keepalived/keepalived.conf        
! Configuration File for keepalived
global_defs {
    notification_email {
        [email protected]
    }
    notification_email_from keepalived@localhost
    smtp_server 127.0.0.1
    smtp_connect_timeout 30
    router_id ka2.magedu.org        # 修改此行
    vrrp_mcast_group4 224.0.100.100
}

vrrp_instance VI_1 {
    state BACKUP            # 此修改行为BACKUP
    interface eth0
    virtual_router_id 66    
    priority 80             # 此修改行为80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 12345678
    }
    virtual_ipaddress {
        10.0.0.10/24 dev eth0 label eth0:1
    }
}
vrrp_instance VI_2 {
    state MASTER                # 修改此行为MASTER
    interface eth0
    virtual_router_id 88        
    priority 100                # 修改此行为100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 12345678
    }
    virtual_ipaddress {
        10.0.0.20/24 dev eth0 label eth0:1  
    }
}

实战案例：利用子配置文件实现master/master的Keepalived双主架构

ka1主机配置

[root@ka1-centos8 ~]#cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   notification_email {
     [email protected]
     [email protected]
     [email protected]
   }
   notification_email_from [email protected]
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id ha1.magedu.org
   vrrp_skip_check_adv_addr
   #vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0

}

include /etc/keepalived/conf.d/*.conf

[root@ka1-centos8 ~]#cat /etc/keepalived/conf.d/cluster1.conf 
vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 66
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        10.0.0.10/24 dev eth0 label eth0:1
    }
    unicast_src_ip 10.0.0.8
    unicast_peer{
        10.0.0.18
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}

[root@ka1-centos8 ~]#cat /etc/keepalived/conf.d/cluster2.conf 
vrrp_instance VI_2 {
    state BACKUP
    interface eth0
    virtual_router_id 88
    priority 80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        10.0.0.20/24 dev eth0 label eth0:1
    }
    unicast_src_ip 10.0.0.8
    unicast_peer{
        10.0.0.18
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}

[root@ka1-centos8 ~]#tree /etc/keepalived/
/etc/keepalived/
├── conf.d
│   ├── cluster1.conf
│   └── cluster2.conf
├── keepalived.conf
├── keepalived.conf.bak
└── notify.sh

1 directory, 5 files

#查看IP
[root@ka1-centos8 ~]#hostname -I
10.0.0.8 10.0.0.10 

ka2主机的配置

[root@ka2-centos8 ~]#cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   notification_email {
     [email protected]
     [email protected]
     [email protected]
   }
   notification_email_from [email protected]
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id ha2.magedu.org
   vrrp_skip_check_adv_addr
   #vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

include /etc/keepalived/conf.d/*.conf

[root@ka2-centos8 ~]#cat /etc/keepalived/conf.d/cluster1.conf 
vrrp_instance VI_1 {
    state BACKUP 
    interface eth0
    virtual_router_id 66
    priority 80
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        10.0.0.10/24 dev eth0 label eth0:1
    }
    unicast_src_ip 10.0.0.18
    unicast_peer {
    10.0.0.8 
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}

[root@ka2-centos8 ~]#cat /etc/keepalived/conf.d/cluster2.conf 
vrrp_instance VI_2 {
    state MASTER
    interface eth0
    virtual_router_id 88
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 123456
    }
    virtual_ipaddress {
        10.0.0.20/24 dev eth0 label eth0:1
    }
    unicast_src_ip 10.0.0.18
    unicast_peer{
        10.0.0.8
    }
    notify_master "/etc/keepalived/notify.sh master"
    notify_backup "/etc/keepalived/notify.sh backup"
    notify_fault "/etc/keepalived/notify.sh fault"
}

[root@ka2-centos8 ~]#hostname -I
10.0.0.18 10.0.0.20

#ka1主机故障，测试VIP漂移至ka2主机
[root@ka1-centos8 ~]#killall keepalived
[root@ka1-centos8 ~]#hostname -I
10.0.0.8 

[root@ka2-centos8 ~]#hostname -I
10.0.0.18 10.0.0.20 10.0.0.10 

#恢复ka1主机
[root@ka1-centos8 ~]#systemctl start keepalived.service 
[root@ka1-centos8 ~]#hostname -I
10.0.0.8 10.0.0.10 
[root@ka2-centos8 ~]#hostname -I
10.0.0.18 10.0.0.20 

实现Keepalived 状态切换的通知脚本

# 在所有keepalived节点配置如下
[root@ka1-centos8 ~]#cat /etc/keepalived/notify.sh 
#!/bin/bash
#
contact='[email protected]'
notify() {
    mailsubject="$(hostname) to be $1, vip floating"
    mailbody="$(date +'%F %T'): vrrp transition, $(hostname) changed to be $1"
    echo "$mailbody" | mail -s "$mailsubject" $contact
}
case $1 in
master)
    notify master
    ;;
backup)
    notify backup
    ;;
fault)
    notify fault
    ;;
*)
    echo "Usage: $(basename $0) {master|backup|fault}"
    exit 1
    ;;
esac

[root@ka1-centos8 ~]#chmod a+x /etc/keepalived/notify.sh