On Wed, Nov 30, 2011 at 11:28:22PM +0000, unruh wrote: > On 2011-11-30, Miroslav Lichvar <mlich...@redhat.com> wrote: > > On Wed, Nov 30, 2011 at 10:24:45PM +0000, unruh wrote: > >> If he has peerstats log file, he can look at it and see what teh offset > >> is of the oncore and the other ntp sources to see if it is really > >> misbehaving that badly. Also, if it is out by 16 sec, why in the world > >> has ntp not stepped the time? The threshold is 128ms. > > > > I think it did step and more than once. I'd suspect a bug in the > > firmware in the GPS-UTC offset handling, current offset is 15 seconds > > and that is visible in one of the ntpq outputs in the original post. > > But how could he get a 16 second offset, after starting out with a .1 s > and 1 s offset. At 500PPM, 16 sec takes 32000 sec (10 hr) to accumulate > which is poll interval 15. Ie, I cannot see how ntpd could have > allowed that huge an offset to occur.
ntpd doesn't step more than once per 15 minutes. What I think was happening: on start the clock is good to couple ms, NTP servers are not reachable yet, but GPS is off by 16s, ntpd steps immediately; GPS is off by 15s, NTP servers are off by 16s, ntpd doesn't step yet; GPS and NTP are off by 16s, ntpd steps back and stabilizes. The loopstats log would be useful. -- Miroslav Lichvar _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
