[time-nuts] Concern over Daylight Saving Time

Jason Rabel jason at extremeoverclocking.com
Sat Jan 20 12:46:12 EST 2007


It probably wouldn't hurt to apply a few upgrades / patches to prevent the
machine from being compromised.

Have you updated the timezone files recently?

Have you tried re-selecting your time zone?

On Redhat machines (and probably others) the zone files are located in:

/usr/share/zoneinfo/....

Then you either symlink or copy the file for your tz to /etc/localtime

Also, I vaguely remember reading that there was some remote date util (maybe
it was rdate) that can specify time for a local time zone (instead of UTC)
and thus a person could be syncing to an improper time without knowing it. I
only use NTP on my machines, and that's what works for me. :)

Jason


-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Didier Juges
Sent: Saturday, January 20, 2007 9:52 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Concern over Daylight Saving Time

Does it mean I should consider upgrading these 2.2.6 linux kernel boxes?
:-)

Joke apart, I would think that in any case, January should not be 
affected by the upcoming change in daylight saving time.

I just wanted to know if anyone had noticed a similar problem.

I have seen the postings about Red Hat, and this is not my problem. 1) I 
use Slackware (yes, no comments please) and 2) system time is wrong 
using the "date" utility in the default mode (runs through timezone). If 
I query system time in UTC (date -u I believe, or something like that), 
it is correct.  In any event, the only applications that run on these 
machines, other than apache and all the goodies that came with Slackware 
(mostly system utilities, these boxes don't even have X, they don't even 
have a monitor attached to them, just ethernet) are programs I wrote (C 
and Perl), and they simply get system time using standard function calls.

I believe the Red Hat patch was simply to link the timezone info to the 
various places that different programs are looking for. In my minimum 
Slackware installation, I have found at least 5 links to timezone (in 
etc, var, lib, usr and a couple of different subdirs). Fortunately, 
there seems to be only one file, all the rest are symlinks.

Maybe the timezone file was bad from the beginning. I'll try MST :-)

Thanks

Didier




More information about the time-nuts mailing list