#! /bin/sh
# pingmon - monitor host up/down status using 'ping'
#
# usage:  pingmon  hostaddress  description  mailaddress...
#
#  also:  entry in crontab file like -
#         3,13,23,33,43,53 * * * * pingmon 1.2.3.4 "VIP host" user1 user2@host2
#
#   Rex Sanders, USGS, February 1992
#   mod 7/95 RS - add description field

host=$1
shift
desc=$1
shift
users=$@

/usr/etc/ping -s $host 56 5 2> /dev/null | \
if grep '100% packet loss$' > /dev/null
then
    # host is down, check to see if it has been down a while
    if [ -f /tmp/pingmon.$host ]
    then
	# host was down, do nothing
	true
	exit 2
    else
	# host just went down, send message and create log
	day=`date '+19%y/%m/%d'`
	time=`date '+%T'`
	( echo "$desc - $host down at $day $time"
	  echo "So sorry, pingmon@"`hostname` ) | \
	      /usr/ucb/mail -s "$desc DOWN at $time" $users
	echo "$desc - $host down at $day $time" > /tmp/pingmon.$host
	exit 1
    fi
else
    # host is up, check to see if it was down
    if [ -f /tmp/pingmon.$host ]
    then
	# host was down, send message and clean up
	day=`date '+19%y/%m/%d'`
	time=`date '+%T'`
	echo					>> /tmp/pingmon.$host
	echo "$desc - $host  UP  at $day $time"	>> /tmp/pingmon.$host
	echo					>> /tmp/pingmon.$host
	echo "Yippy!, pingmon@"`hostname`	>> /tmp/pingmon.$host
        /usr/ucb/mail -s "$desc UP at $time" $users < /tmp/pingmon.$host
	rm /tmp/pingmon.$host
    fi
fi