keepalived 預防腦裂檢測腳本

1 檢查vip

[root@mysql2 keepalived]# cat /etc/keepalived/check_brain_keepalived.sh

#!/bin/bash
# 檢查腦裂的腳本，在備節點上進行部署
LB01_VIP=*
LB01_IP=*
LB02_IP=*
while true
do
  ping -c 2 -W 3 $LB01_VIP &>/dev/null
    if [ $? -eq 0 -a `ip add|grep "$LB01_VIP"|wc -l` -eq 1 ];then
        echo "ha is brain."
    else
        echo "ha is ok"
    fi
    sleep 5
done

運行腳本，在備節點（keepalived的備），不是mysql的備節點

[root@mysql2 keepalived]# ./check_brain_keepalived.sh
ha is ok
ha is ok

由於在M-M+Keepalived環境中，腦裂是一個始終存在的問題，因為vip的存在，這里提供一個腳本進行檢查，檢查vip漂移到備節點

發現backup有vip就發警告，此腳本部署在backup機器上

2 定時ping網關的方法

[root@mysql1 keepalived]# /sbin/arping -I ens192 -c 5 -s * *

#!/bin/bash
host=127.0.0.1
CHECK_TIME=3
VIP=*
GATEWAY=*
eth=ens192
#mysql  is working MYSQL_IS_OK is 1 , mysql down MYSQL_IS_OK is 0
keepalived_IS_OK=1
function check_keepalived_status (){
    /sbin/arping -I $eth -c 5 -s $VIP $GATEWAY >/dev/null 2>&1
    if [ $? = 0 ] ;then
    keepalived_IS_OK=1
    else
    keepalived_IS_OK=0
    fi
    return $keepalived_IS_OK 
}
while [ $CHECK_TIME -ne 0 ]
do
    let "CHECK_TIME -= 1"
    
    check_keepalived_status
if [ $keepalived_IS_OK = 1 ] ; then
    CHECK_TIME=0
   #/bin/systemctl stop keepalived
    echo 1
    exit 0
fi

if [ $keepalived_IS_OK -eq 0 ] &&  [ $CHECK_TIME -eq 0 ]
then
    /bin/systemctl stop keepalived
    echo 0
    exit 1
fi
sleep 3
done