Fedora Time Bug

    December 14, 2005

The question of setting time comes up frequently. Setting the timezone and the system clock can be confusing, particularly if the machine is dual boot.

Nowadays I don’t see too many of those (a sign that Linux has grown up enough or just that it’s cheap enough to run separate machines?), so the answer is usually simple: set the hardware clock to UTC, run ntpd and set your timezone correctly. But for those who want to understand how everything works, http://www.tldp.org/HOWTO/Clock-2.html has all the details. http://www.linuxsa.org.au/tips/time.html is also a useful summary.

So when a local reseller called recently saying he couldn’t get a Fedora Core 4 box to hold time upon reboot, I assumed he just didn’t have things set right and referred him to the docs.

I was wrong. The next thing I heard from the reseller was that he had found a fix.

Apparently there is a current bug with some Intel motherboards: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=144894. To fix, you don’t use UTC on the hardware clock, and you add CLOCKFLAGS=–directisa to the /etc/sysconfig/clock file.

I’m not sure where he found that, and am actually surprised that he did. Googling for anything time related turns up thousands of “hwclock” man pages and duplicates of the LDP docs; it’s hard to sort through all that and find a problem like this. The final comment he had was:

All is working fine now. I think the only problem is that when daylight savings hits, the customer will have to update the bios and the Linux date separately.

*Originally published at APLawrence.com

A.P. Lawrence provides SCO Unix and Linux consulting services http://www.pcunix.com