cron won't recognize time zone change

rl92694 · 09-23-2008, 08:40 AM

We were asked to change the time zone on a bunch of RHEL4 servers from Eastern to Central. So I relinked /etc/localtime, adjusted /etc/sysconfig/clock, and ran "hwclock --systohc". Everything now displays the time as CST.

I then stopped and restarted crond. However, cron still seems to think it's EST. All jobs get started as if it's still EST.

I rebooted one server and it now starts everything at the correct CST time, but I don't want to have to do that on all my servers.

What step am I missing? How do I get crond to recognize the new time zone without rebooting the entire server?

trickykid · 09-23-2008, 10:33 AM

According to the man page:

Quote:

Daylight Saving Time and other time changes
Local time changes of less than three hours, such as those caused by the start or end of Daylight Saving Time, are handled
specially. This only applies to jobs that run at a specific time and jobs that are run with a granularity greater than one
hour. Jobs that run more frequently are scheduled normally.

If time has moved forward, those jobs that would have run in the interval that has been skipped will be run immediately.
Conversely, if time has moved backward, care is taken to avoid running jobs twice.

Time changes of more than 3 hours are considered to be corrections to the clock or timezone, and the new time is used immedi-
ately.

Make sure your changes don't fall into the normal behavior of cron.