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On 03/17/2016 10:59 PM, Bill Kenworthy wrote: |
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> On 18/03/16 05:14, Alan McKinnon wrote: |
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>> On 17/03/2016 22:02, Håkon Alstadheim wrote: |
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>>> On 03/17/2016 02:03 PM, Bill Kenworthy wrote: |
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>>>> On 17/03/16 20:26, Alan McKinnon wrote: |
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>>>>> On 17/03/2016 08:50, Håkon Alstadheim wrote: |
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>>>>>> I have a server SUPPOSED to be running 24/7, but every once in a while |
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>>>>>> during a prolonged absence the box will go down. The Real Time Clock |
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>>>>>> will drift, and in the rush to get the box up again I let everything |
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>>>>>> boot up automatically and get both wrong time on the main systems, and |
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>>>>>> different times on the various systems. |
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>>>>>> |
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>>>>>> My setup has a main server which does NTP, but with no direct link to |
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>>>>>> the outside. Router&firewall /have/ to be booted booted later (dumb |
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>>>>>> setup, don't ask), after which I can finally get correct time from NTP. |
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>>>>>> |
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>>>>>> NTP initiates "11 minute mode", which makes /etc/adjtime useless as far |
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>>>>>> as I understand. Anybody have a /correct/ way to account for RTC drift |
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>>>>>> on a box running ntpd? Right now I have a ---file in |
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>>>>>> /etc/cron.d/time-bad like so: |
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>>>>>> * * * * * root adjtimex -S 5 >/dev/null 2>&1 </dev/null |
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>>>>>> --- |
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>>>>>> |
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>>>>>> Combined with an old-fashioned setup for hwclock during boot and |
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>>>>>> shutdown. This feels really wrong, and I have no idea what I am doing. |
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>>>>>> |
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>>>>>> TLDR: Anybody have a /correct/ way to account for RTC drift on a box |
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>>>>>> running ntpd? |
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>>>>>> |
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>>>>>> |
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> Have you looked at adjtimex ... its in portage |
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> |
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> |
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> From the man page ... |
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> "For a standalone or intermittently connected machine, where it’s not |
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> ossible to run ntpd, |
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I /can/ and do run ntpd once everything is up and running. |
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> you may use adjtimex instead to correct the sys-tem |
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> clock |
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System clock is fine, what I'm after is drift of the RTC clock ("bios |
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clock"). Ntp does nothing for that, as far as I understand. Now, I'd be |
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very happy if someone could tell me I've misunderstood. |
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> for systematic drift. |
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|
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> There are several ways to estimate the drift rate. If your |
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> computer can be connected to the net, you might run ntpd for at least |
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> several hours and run "adjtimex --print" to learn what values of tick |
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> and freq it settled on. Alternately, you could estimate values using as |
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> a reference the CMOS clock (see the --compare and --adjust switches), |
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> another host (see --host and --review), or some other source of time |
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> (see --watch and --review). You could then add a line to rc.local |
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> invoking adjtimex, or configure /etc/init.d/adjtimex or |
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> /etc/default/adjtimex, to set those parameters each time you reboot." |
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> |
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> Used it at one time for dialup which approximates your condition. |
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> |
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> |
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