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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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When the box was off, all questions of accurate ntp tracking are moot. |
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ntp is designed around the idea that every second happens but from your |
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machine's point of view they didn't happen since it was powered down. |
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I would go the really simple route and force ntpdate to run once during |
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boot up before ntpd is started, thereby avoiding the entire issue. |
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Sometimes correctness really doesn't matter, this looks like one of those. |
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alan |
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