[ntp:questions] ntpd: time reset problem

Steve Kostecke kostecke at ntp.org
Thu Sep 17 12:26:55 UTC 2009

On 2009-09-17, Unruh <unruh-spam at physics.ubc.ca> wrote:

> Steve Kostecke <kostecke at ntp.org> writes:
>>The NTP Stable release needs to poll a refclock 4 times before it
>>collects enough data to adjust (i.e. step or slew) the clock. The times
>>you quote are consistant with this.
> A refclock usually has a poll of 4 (16 sec) 4*16=64 sec.


I had to use 'minpoll 4' to reduce the NMEA driver poll interval from 64
sec to 16 sec for my GPS-18LVC.

The CHU refclock driver used by my NET-4801 has a default minpoll of 64.

grepping the ./ntpd directory in the current stable release shows that
refclock_palisade.h is the only place where a driver specific MINPOLL is

Steve Kostecke <kostecke at ntp.org>
NTP Public Services Project - http://support.ntp.org/

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