Re: clock running fast

From: Federico Galvez-Durand Besnard (fico_at_del.ufrj.br)
Date: 12/30/04

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    Date: Thu, 30 Dec 2004 21:34:33 +0100
To: Brooks Davis <brooks@one-eyed-alien.net>

    Brooks Davis wrote:

    >On Thu, Dec 30, 2004 at 11:37:04AM -0800, Javier Henderson wrote:
    >
    >
    >>>>/usr/sbin/ntpd -c /etc/ntp.conf -p /var/run/ntpd.pid \
    >>>>- -f /var/db/ntpd.drift
    >>>>
    >>>>
    >>>It's generally recommended that you never trust your own clock since
    >>>it's completely crap as time sources go. It's also recommended that you
    >>>use at least 5 time sources to avoid problems with bad clocks.
    >>>
    >>>
    >>But isn't that what the drift file is for, to improve the accuracy of
    >>the local clock during those times when the configured NTP servers aren't
    >>available?
    >>
    >>
    >
    >Yes, but it can only do so much. The clock crystals in your average PC
    >are OK as clocks, but much better as thermometers so the drift
    >calculations are only approximate.
    >
    >-- Brooks
    >
    >
    >
    Yeap, but only if your NTPD is running fine and stable, otherwise
    drift-file can be very messy.
    Check your dmesg for NTPD log before you trust drift-files.

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