System Time advances 1 hour each bootup; /etc/localtime linked to non-mounted file?

From: Mark Bergman (mark.bergman_at_thales-is.com)
Date: 04/28/04 

Date: 28 Apr 2004 07:11:59 -0700

I am using Rehat Enterprise Linux 2.1 WS (2.4.9-e.12smp), in
Manchester UK (GMT timezone, currently BST - British Summertime - our
brand of Daylight Savings Time).
Since we entered BST, each time I reboot the machine, the system time
advances by one hour.

/etc/localtime is linked to the appropriate zoneinfo file under /usr.
I have found the "hwclock" commands: in /etc/init.d/halt that stores
the system time to the Hardware clock, and in /etc/rc.sysinit that
sets the system time from the Hardware clock, and I am using the
hardware clock in "localtime" mode (in /etc/sysconfig/clock,
ZONE="Etc/GMT", UTC=false, ARM=false).

By printing the date during bootup (in /etc/rc.sysinit), I see that
the system thinks it is in UTC at the time "hwclock" is called.
I also note that mounting of /usr is not done until later in
rc.sysinit, so presumably /etc/localtime cannot ascertain any timezone
info, and hwclock assumes its "localtime" is UTC, when in fact the
hardware clock is running as BST.

Maybe I could get round this by running the hardware clock in UTC
mode, but I can't see how anyone could get this to work running in
localtime mode!

TIA
Mark Bergman
Thales Information Systems
Manchester UK
mark . bergman @ thales - is . com

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