How to Change the Timezone in Linux

1. Logged in as root, check which timezone your machine is currently using by executing `date`. You’ll see something like Mon Nov 9 13:49:01 EST 2009, PST in this case is the current timezone.
2. Change to the directory /usr/share/zoneinfo here you will find a list of time zone regions. Choose the most appropriate region, if you live in Hong_Kong or the Singapore this directory is the “Asia” directory.
3. If you wish, backup the previous timezone configuration by copying it to a different location. Such as
   mv /etc/localtime /etc/localtime-old
4. Create a symbolic link from the appropiate timezone to /etc/localtime. Example:
   ln -sf /usr/share/zoneinfo/Asia/Hong_Kong /etc/localtime
5. If you have the utility rdate, update the current system time by executing
   /usr/bin/rdate -s time-a.nist.gov
6. Set the ZONE entry in the file /etc/sysconfig/clock file (e.g. “America/Los_Angeles”)
7. Set the hardware clock by executing:
   /sbin/hwclock --systohc