Till Wimmer wrote: > Hi there, > > i try to settle some time accuracy in our office environment... > > Our main server is running SuSE 9.3 on AMD64. I installed the xntp > package from SuSE (Vers. 4.2.0a-35). > Hardware: DELL Power Edge 2850 > > uanme -a: > Linux office 2.6.11.4-21.15-smp #1 SMP Tue Nov 28 13:39:58 UTC 2006 > x86_64 x86_64 x86_64 GNU/Linux > > /etc/ntp.conf: > --- snip --- > driftfile /var/lib/ntp/drift/ntp.drift > > server 127.127.1.0 > fudge 127.127.1.0 stratum 13 > > server 0.debian.pool.ntp.org iburst > server 1.debian.pool.ntp.org iburst > server 2.debian.pool.ntp.org iburst > server 3.debian.pool.ntp.org iburst > > disable auth > --- snap --- > > Short after starting, everythings looks ok: > remote refid st t when poll reach delay offset > jitter > ============================================================================== > > > *typhoon.aput.ne 192.12.19.20 2 u 227 256 377 170.905 -14.600 > 5.776 > +bitvalve.org 192.53.103.108 2 u 166 256 377 32.163 -15.190 > 4.488 > +8.15.10.42 132.163.4.103 2 u 170 256 377 105.118 -11.706 > 3.857 > -ns.oredin.net 193.190.230.66 2 u 179 256 277 141.835 36.960 > 17.438 > LOCAL(0) LOCAL(0) 13 l 49 64 377 0.000 0.000 > 0.001 > > But after 3..5 hours all peers are rejected (ntpq> as) and LOCAL(0) is > the sync source. > > I checked the firewall, disabled all restrict settings, disabled chroot > and running as unprivileged user, a.s.o. > > Now i found that pps stability is always 512ppm and pll has a huge offset. > > ntpdc> kern: > pll offset: 4294.95 s > pll frequency: 22.694 ppm > maximum error: 0.364061 s > estimated error: 0.017754 s > status: 0001 pll > pll time constant: 4 > precision: 1e-06 s > frequency tolerance: 512 ppm > pps frequency: 0.000 ppm > pps stability: 512.000 ppm > pps jitter: 0.0002 s > calibration interval: 4 s > calibration cycles: 0 > jitter exceeded: 0 > stability exceeded: 0 > calibration errors: 0 > > I set the hwclock -w and started fro scratch, but short after the offset > was the same. > I can't believe that the clock of this server is this terribly > inaccurate... IMHO it's "professional" hardware. At least it was > expensive ;) > > Any help would be very much appreciated! > Till >
Three of your servers have round trip delays that are extreme by most standards. Try to find servers closer to you. I don't use pool servers myself but I believe that you can select regional servers by; e.g. us.pool.ntp.org for servers in the United states eu.pool.ntp.org for servers in Europe etc. Twenty milliseconds round trip delay is a good number. Make every effort to stay below thirty milliseconds. _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
