[lug] laptop time

Installer jkarns at csd.net
Thu Feb 22 07:53:23 MST 2001

On Wed, 21 Feb 2001, Timothy C. Klein said:

>Set your bios to GMT (or UTC, whatever you call it).  I suspect your
>problem will go away.  If you run only linux, to do this adjust your
>time to the correct time for MST, (rdate -s time.nist.gov is easy), then
>do hwclock --systohc to sync the RTC in your laptop with that.
>I don't think you have to tell Linux that the RTC is in UTC (he he,
>funny acronyms), but I could be wrong.  If that doesnt help, let me
>know.  It is early in the morning and I am still sleepy.  You also need
>to make sure that you run tzconfig and set your timezone correctly, so
>that when linux asks for the time, it gets UTC first, and converts it to
>local time for you.
>If you run Windows on the laptop, you may have to lie Linux about which
>timezone you are (I would tell it you are in GMT), and make sure the
>bios is set to local time.  But I don't like that approach.

This has always been a little bit fuzzy for me.  Are you saying that you
can set the CMOS clock to local time but have the Linux RTC run in
GMT?  How would this affect timestamping in the filesystem?  I once tried
setting the CMOS clock to RTC as recommended in one of the Howto's, but
then it becomes a source of confusion when looking at fs timestamps, and
also affects cron etc.  

Here near the equator, the seasonal time changes for daylight savings is
not an issue, because it doesn't exist.  This is given as a reason for
using GMC in the kernel configuration help doc.

If I could have the RTC transparently use GMT, I think that may be

John Karns                                              jkarns at csd.net

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