To set the timezone in Linux, update /etc/localtime with the appropriate timezone file from /usr/share/zoneinfo.
rm -f /etc/localtime
ln -sf /usr/share/zoneinfo/America/Los_Angeles /etc/localtime
This would set your time zone to PST/PDT (Pacific Time) because that is the time zone Los Angles is located in....
By steve, January 24, 2015