[ntp:questions] Ginormous offset and slow convergance
unruh at invalid.ca
Wed Nov 30 17:15:52 UTC 2011
On 2011-11-30, Pete Ashdown <pashdown at xmission.com> wrote:
> David Woolley <david at ex.djwhome.demon.invalid> writes:
>>Richard B. Gilbert wrote:
>>> On 11/29/2011 1:42 PM, Pete Ashdown wrote:
>>>> +time-C.timefreq .ACTS. 1 u 19 64 377 37.887
>>>> -16011. 0.122
>>>> Is there anything I can do to decrease the convergence time?
>>> Little or nothing! NTPD can, and sometimes does, take ten hours to
>>> reach "steady state". It needs about thirty minutes to find a
>>16 second excursions are not the result of ntpd convergence delays.
>>They indicate something seriously broken. Possibly something else is
>>trying to set the time.
> Thanks for the pointer David. I added the local hardware clock (127.127.1.0)
> to the ntp.conf and that nailed it down. Now my convergence is under a
One problem in the sequence you showed was that your oncore gps started
off 1 second out from "true time". It then seems to have corrected
itself. This may well have confused ntpd into
starting a huge drift correction, which then played itself out. I do not
understand why the 128ms rule did not get applied.
Certainly having a refclock be inconsistant to the 1 second level would
not do good things for ntpd.
More information about the questions