! Configuration File for keepalived

global_defs {
   router_id LB111
}

vrrp_script chk_nginx {
   # 具體的腳本
   script "/etc/keepalived/nginx_check.sh"
   interval 2 # 2s執(zhí)行一次 
   weight -20 # 失敗一次 則優(yōu)先級(jí) -20
}

vrrp_instance VI_1 {
    state MASTER
    interface ens160
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.16.225.200
    }
    # 指定腳本
    track_script {
      chk_nginx
    }
}

! Configuration File for keepalived

global_defs {
   router_id LB111
}

vrrp_script chk_nginx {
   script "/etc/keepalived/nginx_check.sh"
   interval 2
   weight -20
}

vrrp_instance VI_1 {
    state BACKUP
    interface ens160
    virtual_router_id 51
    priority 90
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
       172.16.225.200
    }

    track_scrip {
      chk_nginx
    }
}

#!/bin/bash
status=$(ps -C nginx --no-heading|wc -l)
if [ "${status}" = "0" ]; then
            # 嘗試啟動(dòng)一次
            systemctl start nginx
        # 再次檢查ngixn 進(jìn)程
        status2=$(ps -C nginx --no-heading|wc -l)
        if [ "${status2}" = "0"  ]; then
                # 關(guān)閉 keepalived 
                systemctl stop keepalived
        fi
fi

# 給腳本一個(gè) 可執(zhí)行的權(quán)限
chmode +x /etc/keepalived/nginx_check.sh 

# 重啟或者啟動(dòng) keepalived 
systemctl restart keepalived

# 臨時(shí)關(guān)閉
setenforce 0

#永久關(guān)閉
sed -i 's/SELINUX=enforcing/\SELINUX=disabled/' /etc/selinux/config

# 關(guān)閉 nginx 
./nginx -s stop

# 此時(shí)查看 keepalived 的狀態(tài)就是 dead了
systemctl status keepalived

● keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; disabled; vendor preset: disabled)
   Active: inactive (dead)