Shell脚本监控WEB服务是否正常

#!/bin/bash
#====================================================
# Author: lizhenliang - EMail:zhenliang369@163.com
# Last modified: 2015-2-1 
# Filename: web_mon.sh
# Description: wget monitoring web is normal 
# blog:lizhenliang.blog.51cto.com
#====================================================
while true
do
    Mail="baojingtongzhi@163.com" 
    FailCount=0
    Retval=0
    GetUrlStatus() {
    for ((i=1;i<=3;i++))     #使用i++判断访问次数，如果wget两次超时则判断网站异常
    do
        wget -T 3 --tries=1 --spider http://${1} >/dev/null 2>&1
        #-T超时时间，--tries尝试1次，--spider蜘蛛
        [ $? -ne 0 ] && let FailCount+=1;    #访问超时时，$?不等于0，则FailCount加1
    done
    if [ $FailCount -gt 1 ];then
        Retval=1
        Date=`date +%F" "%H:%M`
        echo -e "Date : $Date\nProblem : $url is not running." | mutt -s "URL Monitor" $Mail
    else
        Retval=0
    fi
        return $Retval        #如果返回值为0，就正常退出循环，不为0则继续循环
     }
for url in `cat url | sed '/^#/d'`
do
    #GetUrlStatus $url && echo yes || echo no
    GetUrlStatus $url
done
sleep 2m            #死循环，设置没2分钟运行一次
done