[ntp:questions] Using both Server and Peer in ntp.conf
Uwe Klein
uwe_klein_habertwedt at t-online.de
Thu Feb 8 20:25:45 UTC 2007
Hal Murray wrote:
>>How many minutes, hours, or days of "holdover" with reasonably correct
>>time you may get depends on the quality of the local clock, the
>>stability of the temperature, the phase of the moon and the whims of the
>>gods!
>
>
> We can at least do a bit of arithmetic.
>
> There are 86400 seconds in a day. If your clock is off
> by 11 ppm, it will drift 1 second per day.
>
> If your machine is in an airconditioned machine room, the
> average temperature is probably pretty stable. I'd guess
> a second per week would be conservative.
>
> If your machine is in an environment with poor temperature
> regulation, the day to day average temperature is probably
> the important consideration.
>
Yes it works that way, I have systems ( embedded, linux + RT )
running in a reasonably climatised room that have to do exactly
18000 sample cycles per 30min interval. When I have fixed
the timer value to make it fit I can leave it alone for quite
some time : weeks, month,..
But I get an imediate error when the gas tank for the heating is
empty ;-)
To return to my question:
Does ntpd follow this deterioration in any way?
uwe
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