PF双线负载均衡完美解决方案(带链路状态监控)...

#!/bin/sh

#write by loulancn#163.com

#定义两个出口的网关

gw1=192.168.6.1
gw2=192.168.15.1

#负载均衡和单线路故障时的pf规则

PF_Load_Balance=/etc/pf/PF_Load_Balance.conf
PF_Lan1=/etc/pf/PF_Lan1.conf
PF_Lan2=/etc/pf/PF_Lan2.conf

#记录链路状态和线路故障的事件

Link_State=/etc/Link_State
Link_State_Log=/var/log/Link_State_Log

#获取上一次的状态值

Previously_Link_State=`cat $Link_State`

#程序开始

if ping -c1 -W1 $gw1 >/dev/null 2>&1
then
  if ping -c1 -W1 $gw2 >/dev/null 2>&1
        then
        L_State=2
        echo $L_State > $Link_State
        else
        L_State=1
        echo $L_State > $Link_State
        fi
else
        if ping -c1 -W1 $gw2 >/dev/null 2>&1
        then
        L_State=0
        echo $L_State > $Link_State
        else
        L_State=-1
        echo $L_State > $Link_State
        fi
fi

if [ $Previously_Link_State -eq $L_State ]
then
echo " Link State Not Change !"
else

        case $L_State in
        2)
        echo "All Link is UP at `date`! " >> $Link_State_Log
 pfctl -f $PF_Load_Balance
        ;;

        1)
        echo "Link $gw1 is UP! Link $gw2 is Down at `date`!" >> $Link_State_Log
 
 #单线路时对默认路由的修改
 route delete default
 route add default $gw1

 pfctl -f $PF_Lan1
        ;;

        0)
        echo "Link $gw1 is Down ! Link $gw2 is UP at `date`!" >> $Link_State_Log
 route delete default
 route add default $gw1
 pfctl -f $PF_Lan2
        ;;

        -1)
        echo "All Link is Down at `date`!" >> $Link_State_Log
        ;;
        esac

fi