#!/bin/sh

# 2014/04/10 Lisa
# Modified this script to use the usn pool from pool.ntp.org. More
# Info on this can be found at the project page: http://www.pool.ntp.org/zone/us

if [ -d /proc/sys/xen ]; then
   echo 1 > /proc/sys/xen/independent_wallclock;
fi

servers='0.us.pool.ntp.org 1.us.pool.ntp.org 2.us.pool.ntp.org 3.us.pool.ntp.org'


/usr/sbin/ntpdate $servers >/dev/null 2>&1
rc="$?"

if [ $rc -ne 0 ] ; then
   /usr/sbin/ntpdate $servers 2>&1 \
   | grep -q ': the NTP socket is in use, exiting$'
if [ $? -eq 0 ] ; then
   exit 0          # machine is running NTP daemon
fi
	for backoff in 15 30 60 300 ; do
	sleep $backoff
	/usr/sbin/ntpdate $servers >/dev/null 2>&1
	rc="$?"
	[ $rc -eq 0 ] && break
	done
fi

if [ $rc -ne 0 ] ; then
   echo "ntpdate failed, trying again"
   # try again, and be verbose
   date
   ping -c 3 $servers
   /usr/sbin/ntpdate $servers 2>&1
   if [ $? -ne 0 ] ; then
   # DNS failure?
   sleep 300
   date
   ping -c 3 $servers
   /usr/sbin/ntpdate $server 2>&1
if [ $? -ne 0 ] ; then
   exit
   fi
   fi
   fi

if [ -e /dev/rtc ]; then
   /sbin/hwclock -w
fi