The system time is often a symlink to the file /etc/localtime or the time zone file on the time zone directory. The definition for time zones can be written in short form as UTC±n (or GMT±n), where n is the offset in hours.
Set time
To view current date and time type “date” in your terminal or ssh session. Use “date” to update date and time, remember you need to be root to do this.
# date Mon Dec 5 08:07:30 EST 2011
To set a new date and time: date –set=”STRING”
# date --set="6 DEC 2011 08:10:00" Tue Dec 6 08:10:00 EST 2011
Change timezone
To change timezone we need to create a symlink to /etc/localtime from the new timezone in /usr/share/zoneinfo/
To set to CET:
# cd /etc/ # rm -f localtime # ln -sf /usr/share/zoneinfo/Europe/Stockholm localtime # date Mon Dec 5 14:15:02 CET 2011
Change timezone in PHP
date_default_timezone_set('Europe/Stockholm');
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