#!/bin/sh

IP="66.230.156.1"
ADDRESS="email@address.com"
DEBUG=1

state="up"

while true
do
  if [ "$DEBUG" != "" ]; then
     echo "o `date` : Testing $IP"
  fi

  RES=`fping $IP`

  GRP=`echo $RES | grep alive | wc -l`

  if [ $GRP -lt 1 ]; then # must be down
    if [ "$state" = "down" ]; then #must have been down before
       notify=0;
    else
       notify=1;
       state="down"
    fi

     if [ "$DEBUG" != "" ]; then
        echo "o `date` : Test results : Target is $state"
     fi
  else

    if [ "$state" = "up" ]; then #must have been up before
      notify=0;
    else
      state="up"
      notify=1;
    fi

     if [ "$DEBUG" != "" ]; then
        echo "o `date` : Test results : Target is $state"
     fi
  fi



    if [ $notify -gt 0 ]; then
       DT=`date`
       echo | mail -s "$IP is $state" $ADDRESS
    fi

  sleep 300
done