扫描局域网ip的shell

# vim /mysh/ipscan.sh 

#!/bin/bash

# scan the local alive ipaddress

# --

if [ -f $filename ];then

   echo "the file is exist"

 for n in {..};do

      host=192.168..$n

      ping -c2 $host &>/dev/null

      if [ $? =  ];then

         echo "$host is up"

         echo "$host" >> /root/alive.txt

      else

          echo "$host is Down"

      fi

   done

      echo "------------------`date +"%Y-%m-%d"`-------------------------------"

 else

   echo "the file is not exist"

   touch /root/alive.txt

fi