Fixing Time Sync problem in Xen DOMU on Oracle VM Server

A 0 in the following suggests syncing time with DOM0:
/proc/sys/xen/independent_wallclock

However, when DOMU is unable to keep time sync with DOM0, the following may be tried:
echo 1 > /proc/sys/xen/independent_wallclock

If you have a ntpd setup elsewhere:
/usr/sbin/ntpdate <ntpd_server>

To update over the network:
rdate -s http://time-a.nist.gov

To manually set the date:
date -s "<date>

Updating Time Zone in Linux

Following should work on RHEL, Oracle Linux, Centos, Ubuntu, and similar may work on others:
Update /etc/sysconfig/clock with the desired timezone from /usr/share/zoneinfo
Backup current localtime:
mv /etc/localtime /etc/localtime.o
cp /usr/share/zoneinfo/ /etc/localtime

If the command is available, the above can be achieved by using:
system-config-date