On May 30, 1:05 pm, "Richard B. Gilbert" <[EMAIL PROTECTED]> wrote: > Dave wrote: > > On May 25, 9:28 am, Dave <[EMAIL PROTECTED]> wrote: > > >>On May 24, 8:09 pm, "Richard B. Gilbert" <[EMAIL PROTECTED]> > >>wrote: > > >>>Dave wrote: > > >>>>On May 23, 1:16 pm, "Richard B. Gilbert" <[EMAIL PROTECTED]> > >>>>wrote: > > >>>>>Dave wrote: > > >>>>>>I'm experiencing large values of dispersion when I use 'ntpq -p': > > >>>>>>3:22pm:ntp>ntpq -p > >>>>>> remote refid st t when poll reach delay > >>>>>>offset disp > >>>>>>============================================================================== > >>>>>>*10.2.100.10 .GPS. 1 u 25 64 377 0.46 > >>>>>>943.557 439.36 > >>>>>>3:22pm:ntp> > > >>>>>>but when I look at the peerstats log file, my dispersion is low: > > >>>>>>3:22pm:ntp>tail /var/ntp/ntpstats/peerstats.log > >>>>>>54243 54804.018 10.2.100.10 9634 0.617563 0.00046 0.31154 > >>>>>>54243 54868.013 10.2.100.10 9634 0.813226 0.00043 0.32210 > >>>>>>54243 54932.018 10.2.100.10 9634 0.099169 0.00046 0.55225 > >>>>>>54243 54996.010 10.2.100.10 9634 0.300057 0.00047 0.28690 > >>>>>>54243 55060.014 10.2.100.10 9634 0.584358 0.00044 0.31111 > >>>>>>54243 55124.009 10.2.100.10 9634 0.781632 0.00047 0.32353 > >>>>>>54243 55188.014 10.2.100.10 9634 0.065932 0.00043 0.55287 > >>>>>>54243 55252.013 10.2.100.10 9634 0.657674 0.00044 0.37859 > >>>>>>54243 55316.018 10.2.100.10 9634 0.943557 0.00046 0.43936 > >>>>>>54243 55380.013 10.2.100.10 9634 0.139388 0.00044 0.59772 > >>>>>>3:23pm:ntp> > > >>>>>>I'm also concerned with the large amount of maximum/estimated error > >>>>>>when I use the xntpdc command 'kerninfo': > > >>>>>>xntpdc> kerninfo > >>>>>>pll offset: 0 us > >>>>>>pll frequency: -391.137 ppm > >>>>>>maximum error: 524704 us > >>>>>>estimated error: 408368 us > >>>>>>status: 0089 > >>>>>>pll time constant: 2 > >>>>>>precision: 1 us > >>>>>>frequency tolerance: 512 ppm > >>>>>>pps frequency: 0.000 ppm > >>>>>>pps stability: 512.000 ppm > >>>>>>pps jitter: 200 us > >>>>>>calibration interval: 4 s > >>>>>>calibration cycles: 0 > >>>>>>jitter exceeded: 0 > >>>>>>stability exceeded: 0 > >>>>>>calibration errors: 0 > >>>>>>xntpdc> > > >>>>>>Here is the output of the pstats command: > > >>>>>>xntpdc> pstats 10.2.100.10 > >>>>>>remote host: 10.2.100.10 > >>>>>>local interface: 10.2.100.5 > >>>>>>time last received: 3s > >>>>>>time until next send: 61s > >>>>>>reachability change: 2947s > >>>>>>packets sent: 59 > >>>>>>packets received: 59 > >>>>>>bad authentication: 0 > >>>>>>bogus origin: 0 > >>>>>>duplicate: 0 > >>>>>>bad dispersion: 15 > >>>>>>bad reference time: 0 > >>>>>>candidate order: 1 > >>>>>>xntpdc> > > >>>>>>And lastly, my ntp.conf file: > > >>>>>>3:25pm:inet>more ntp.conf > >>>>>>server 10.2.100.10 # NTP server > > >>>>>>driftfile /etc/ntp.drift # Drift available for next restart > >>>>>>logfile /var/ntp/ntp.log # NTP logging > > >>>>>>statsdir /var/ntp/ntpstats/ > >>>>>>statistics loopstats peerstats clockstats > >>>>>>filegen loopstats file loopstats.log type day link enable > >>>>>>filegen peerstats file peerstats.log type day link enable > >>>>>>filegen clockstats file clockstats.log type day link enable > >>>>>>3:25pm:inet> > > >>>>>>Anyone have any ideas? I have a GPS signal coming in to a Brandywine > >>>>>>NTA-100, which is configured at 10.2.100.10. Thanks in advance! > > >>>>>If you are using "X"ntpdc you would appear to be using a version that > >>>>>may be as much as ten years old! Just what are you using and what are > >>>>> you running it on? > > >>>>Wow you're right. Heres the version printout: > >>>>xntpdc 3-5.93e Mon Sep 20 15:47:24 PDT 1999 (1) > > >>>>I'm running this on a Sun Fire 4200, Solaris 10. Something this old > >>>>comes installed on Solaris 10? > > >>>Yup! > > >>>I think it has something to do with the fact that there is, as yet, no > >>>RFC for NTP V4. There is a committee, God help us, working on one. I > >>>think it has been about a year now with no visible results! > > >>>I'd suggest grabbing a more recent version of the code from somewhere. > >>>Sun Freeware and Blastwave sites should both have Solaris versions more > >>>recent than what Sun ships. There have been quite a few fixes and > >>>enhancements since 3-5.93e. > > >>>If you want/are able to build your own, try the ntp.org web site; there > >>>are links there to download the source to the stable and development > >>>versions which are, I believe, at 4.2.something. > > >>I just downloaded ntp v4.2.4 from sunfreeware.com and I'll give that a > >>try. I'll let you know how it goes! > > > Ok so I have the new version loaded and its been running for about 24 > > hours now. I still have a large amount of jitter (reported on by ntpq - > > p): > > 2:50pm:freadd_user>ntpq -p > > remote refid st t when poll reach > > delay offset jitter > > ======================================================== > > *10.2.100.10 .GPS. 1 u 3 64 377 0.461 > > 91.914 385.406 > > <snip> > > > Do I need to worry about the jitter value from ntpq -p, or does > > everything look okay? > > Looking a little more carefully at your ntpq banner it looks as if the > delay (round trip delay) to your server is unreasonably large. You're > using an RFC-1918 address which is a private network but the delay > suggests that the server is a couple of thousand miles away or that you > are using tin cans and string to communicate with it. > > The potential error in transmitting the time from server to client is > one half the round trip delay. This, in turn, suggests that minimizing > the round trip delay is a good idea. I don't know how to account for a > delay like this in what is presumably a small LAN. Can you explain it?
Thanks, Steve for explaining that. I tried to condense it when I copy/ pasted it, and it looked fine in the original text window. Sorry about the confusion. Even so, if you're still wondering, I have a GPS antenna feed coming into the NTA-100 and ethernet out to a switch (approx 6 feet of cable). Thanks for all the help _______________________________________________ questions mailing list [email protected] https://lists.ntp.isc.org/mailman/listinfo/questions
