Re: [SLE] ntpd seems to work but how well?

From: John Andersen (jsa_at_pen.homeip.net)
Date: 09/02/04

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    To: suse-linux-e@suse.com
    Date: Wed, 1 Sep 2004 23:51:30 -0800
    
    
    

    On Wednesday 01 September 2004 05:11 am, Gonda Brouerius van Nidek wrote:
    > I have read the info on ntpd several times and I think I understand
    > the basics. I hope I have ntpd working on my dialup system with 9.1.
    >
    > One of the possibilities to see if it really works should be to use
    > ntpq -p
    > I get the following output with this command but apart from
    > recognizing the four addresses that I have chosen I do not understand
    > the meaning of the output.
    > Somebody with an explanation in plain English?
    >
    >
    > # ntpq -p
    > remote refid st t when poll reach delay offset jitter
    > =====================================
    > 202.180.0.71 .INIT. 16 u - 64 0 0.000 0.000 4000.00
    > my1.doubleukay. 192.6.38.127 2 u 40 64 1 1039.17 -183.26 0.002
    > ns01.deu.edu.tr .INIT. 16 u 49 64 0 0.000 0.000 4000.00
    > darkstar.sanet. 212.82.32.15 2 u 58 64 1 908.414 -82.537 0.002

    How long did you wait after starting ntpd to check these numbers?

    It takes a while to sync you know. 5 to 10 minutes.

    After a bit you will see an asterisk on one of the clock lines.
    That means its synced with that clock.
    From then on it will be dead on perfect. (for some definitions of perfect).

    It will try to sync with a clock in the highest strata (smallest ST number)
    that has the lowest Delay. But it sometimes will select another clock
    by some hocus pocus I don't understand.

    By the way, your machine will never sync if its clock is off by a LOT,
    so get it close before you start.

    Your ISP should supply a strata 2 or 3 clock, and that is usually the one to
    use, but some ISPs dont do it, or let theirs get hopelessly out of sync.
    Generally its recommend you NOT use one of the strata 1 clocks because
    if everybody did, it would get overloaded. There are lists of clocks on
    the internet somewhere. Google will find them, or look here:
    http://www.ntp.org/
    http://www.eecis.udel.edu/~mills/ntp/servers.html
    http://www.ntp.org/ntpfaq/NTP-a-faq.htm

    -- 
    _____________________________________
    John Andersen
    
    



  • Next message: John Andersen: "Re: [SLE] IBM hard drive"

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