[ntp:questions] once 'ntpd' stops, does the drift file value continue to get used for clock adjustments?

Martin Burnicki martin.burnicki at meinberg.de
Fri Mar 18 08:38:51 UTC 2011

David Woolley wrote:

> Gautam Thaker wrote:
>> I have a stable drift value on my fedora 12 node and everything is
>> running well. (offsets are well below 1msec). If I now stop 'ntpd'
>> will my time start to drift relative to the 'correct time' by the PPM
>> value in the drift file? Or is it that ntpd has already set things up
> Depends on whether or not you are using the kernel time discipline.
> Some people set tinker values that cause the kernel discipline to be
> turned off, and it is not supported on all platforms.
> Windows will probably retain the last correction, but this may include a
>   high frequency component.

AFAIK the Windows port of ntpd restores the standard tick value when it
terminates, so the drift compensation isn't in effect anymore thereafter.

Martin Burnicki

Meinberg Funkuhren
Bad Pyrmont

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