Here are some examples to change the timezone to Pacific or Eastern Using_AMPs command line.
# ln -sf /usr/share/zoneinfo/US/Pacific /etc/localtime
# ln -sf /usr/share/zoneinfo/US/Eastern /etc/localtime
The timezone under Linux is set by a symbolic link from /etc/localtime to a file in the /usr/share/zoneinfo directory that corresponds with what timezone you are in. For example, if I'm in South Australia, /etc/localtime is a symlink to /usr/share/zoneinfo/Australia/South. To set this link, type:
ln -sf /usr/share/zoneinfo/your/zone /etc/localtime
Have a look in the directories under /usr/share/zoneinfo to see what timezones are available.