Server Patches and Time Zones

Sometimes, after a server patch, the timezone is reset to Pacific time.  Why?  I don’t know, but when you patch a machine, be sure to double-check that the time zone after the patch is the same as before the patch.  If not, set it.

1. Logged in, then su, check which timezone your machine is currently using by executing `date`. You’ll see something like Mon 17 Jan 2005 12:15:08 PM PST, 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 Canada or the US this directory is the “America” 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 appropriate timezone to /etc/localtime. Example:
   ln -sf /usr/share/zoneinfo/Europe/Amsterdam /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

Tags: hwclock, sbin, sysadmin, sysconfig, timezone