ping test shell script

bash shell

#!/bin/bash
HOST=./pinglist
num="0"

echo "[$(date)] start ping check!!"
#echo "" > ./ping_fail.log
cat /dev/null > ./ping_fail.log
cat /dev/null > ./pinglist.fail

for ABC in `cat ${HOST}`
do
    num=`expr $num + 1`
    CHK=`echo ${ABC} | cut -c 1`
    if [[ ${CHK} != '#' ]]; then

        ping -c 1 -t 1 -W 1 ${ABC} &> /dev/null
        if [ "$?" == "0" ];
        then
            echo "[$num] ${ABC} OK" >> ./ping_fail.log
        else
            echo "${ABC}" >> ./pinglist.fail
            echo "[$num] ${ABC} Fail" >> ./ping_fail.log
       fi
    fi
done

echo "[$(date)] end ping check!!"
cat ./ping_fail.log