color ping result, and save log file

ping.sh

#!/bin/bash

# argument validation
if [ $# -eq 2 ];then
  target=$1
  interval=$2
  log="`/bin/date +%Y%m%d%H%M%S`_`/bin/hostname -i`---$1_ping.log"
else
  echo -e "USAGE: ./ping.sh <IP_ADDRESS or HOSTNAME> <PING_INTERVAL[sec]>\n"
  exit 1
fi

error_count=0

is_alive_ping()
{
  /bin/ping -c 1 -i $2 -w 1 $1 > /dev/null
  if [ $? -eq 0 ]; then
    echo -e "\e[32mOK\e[m --- `date "+%b %d %R:%S.%N"` : Node with IP( $1 ) is up."   | tee -a $3
    return 0
  else
    echo -e "\e[31mNG\e[m --- `date "+%b %d %R:%S.%N"` : Node with IP( $1 ) is down." | tee -a $3
    return 1
  fi
}

trap_ctrl_c()
{
  echo -e "\n***** end ping *****\n"
  echo -e "\nerror: $error_count" | tee -a $log
  exit 0
}


# ----------------------------------------------------------------------
trap trap_ctrl_c SIGINT

i=1
while true;
do
  printf "$((i++))\t\t: "
  is_alive_ping $target $interval $log
  let error_count=$error_count+$?
  sleep $interval
done