NTP客户端时间同步的脚本

#!/bin/sh

#ntpupdate.sh

#set you ntpserver ip address

NTPSERVERIP=""

LOGINNAME=`whoami`

NTPSERVER_CHECK=`ntpdate -q $NTPSERVERIP >/dev/null 2>&1;echo $?`

NTP_CHECK=`netstat -ln|grep 123|wc -l`

function permsg ()

{

   echo ""

   echo "You need to be root to run this script!!"

   echo ""

}

function ntpmsg ()

{

   echo ""

   echo "WARNING:You Can't Execute ntpdate Or Your Ntpserver Down!!"

   echo ""

}

function servermsg()

{

   echo ""

   echo "WARNING:This is NTPSERVER!!"

   echo ""

}

#if the user is not root

if [ "$LOGINNAME" != "root" ]

  then

     permsg

     exit 1

fi

if [ $NTP_CHECK -ne 0 ]

  then

     servermsg

        exit 1

fi

if [ $NTPSERVER_CHECK -ne 0 ]

  then

    ntpmsg

    exit 1

fi

#create crontab

crontab -l >/tmp/root.cron.tmp

sed '/\/usr\/sbin\/ntpdate/d'  /tmp/root.cron.tmp > /tmp/root.cron

echo "* */1 * * * /usr/sbin/ntpdate $NTPSERVERIP;hwclock -w>/dev/null 2>&1" >>/tmp/root.cron

crontab /tmp/root.cron

#start ntpdate

/usr/sbin/ntpdate $NTPSERVERIP >/dev/null 2>&1

##start ntpdate when os start

COUNT=`cat /etc/rc.d/rc.local|grep ntpdate|wc -l`

if [ $COUNT -eq 0 ]

   then

     echo "### start ntpdate " >> /etc/rc.d/rc.local

     echo "/usr/sbin/ntpdate $NTPSERVERIP;hwclock -w">>/etc/rc.d/rc.local

fi