netbsd-help: Re: ntpd: 512 PPM exceeds tolerance

Subject: Re: ntpd: 512 PPM exceeds tolerance
To: rudolf <netbsd@eq.cz>
From: Chuck Swiger <cswiger@mac.com>
List: netbsd-help
Date: 08/14/2005 15:19:05

rudolf wrote:
> I've got a dual-opteron machine here and have some problems with ntpd. 
> Everything is fine when the machine does nothing, but when there is some 
> load (cvs, rsync), it starts to log 'frequency errors'. Is it serious? 
> NetBSD 2.0_STABLE.
It looks like two or more of your upstream NTP sources disagree about time to 
such an extent that they are swinging your clock back and forth. Either that, 
or maybe your mainboard's hardware clock is busted.
Run ntpq and then the peers command, and see whether two or more servers have a 
significant offset. I run a ring-of-three NTP servers as peers, each syncing 
to a seperate major timesource (like time.apple.com, nist.gov, etc) and a 
pool.ntp.org random IP:
ntpq> peers
 remote refid st t when poll reach delay offset jitter
==============================================================================
+thesimonet.org 140.142.16.34 2 u 79 512 377 131.341 1.217 1.188
+NAVOBS1.MIT.EDU .PSC. 1 u 142 512 377 10.561 5.535 0.187
*bonehed.lcs.mit .CDMA. 1 u 75 512 377 10.189 5.419 0.199
+time.apple.com 17.106.100.13 2 u 75 512 377 83.711 4.322 0.496
 shot 199.103.21.227 3 u 291 1024 375 0.367 -3.970 1.191
xpublic 18.145.0.30 2 u 144 512 377 0.441 -13.588 0.091
-ns1 63.73.218.130 2 u 286 1024 176 0.150 1.171 0.291
-- 
-Chuck