#!/bin/sh
while true
do
    _o=$_h
    ping -qn -w1 -c1 $1 > /dev/null 2>&1
    _h=$?
    if [ x"$_o" != x"$_h" ];
    then
        [ $_h -eq 0 ] && echo "Host is up"
        [ $_h -eq 1 ] && echo "Host is down"
    fi
    sleep 2
done