> From: Unruh <[EMAIL PROTECTED]> > Date: Tue, 23 Sep 2008 20:05:48 GMT > Sender: [EMAIL PROTECTED] > > > Steve Kostecke <[EMAIL PROTECTED]> writes: > > >On 2008-09-23, Kevin Oberman <[EMAIL PROTECTED]> wrote: > > >>"Steve Kostecke" <[EMAIL PROTECTED]> wrote: > >> > >>> On 2008-09-23, Kevin Oberman <[EMAIL PROTECTED]> wrote: > >>> > >>> > [---=| Quote block shrinked by t-prot: 40 lines snipped |=---] > >>> > > >>> >> It would be helpful to know the exact NTP version, and which > >>> >> hardware clock and refclock driver was used. > >>> > > >>> > It's 4.2.4p4 running on FreeBSD 7.0. The reference clock is a > >>> > EndRun Tech CDMA clock using the TrueTime driver. When the system > >>> > was running, ntpq claimed no successful polls of the reference > >>> > clock or the PPS. It was getting good responses from other systems, > >>> > but not syncing to them. > >>> > >>> The ntpq peer billboard you posted shows that ntpd _has_ chosen > >>> another system as the sys_peer. See below. > >> > >> Yes, that is quite clear. > > >The sys_peer is the time source that this ntpd is "synced" to. > > >>> > remote refid st t when poll reach delay offset jitter > >>> >================================================================= > >>> >TRUETIME(1) .CDMA. 0 l - 16 0 0.000 0.000 0.001 > >>> >PPS(1) .PPS. 0 l - 16 0 0.000 0.000 0.001 > >>> >-time1-owamp.es. .PPS. 1 u 17 64 177 2.058 -10.335 0.038 > >>> >*time2-owamp.es. .PPS. 1 u 49 64 177 24.556 -10.408 0.020 > >>> >-time3-owamp.es. .PPS. 1 u 63 64 176 55.640 -10.337 0.049 > >>> >+time4-owamp.es. .PPS. 1 u 59 64 176 20.770 -10.405 0.058 > >>> > >>> Is there something about this system which is different from the other > >>> time servers? > >> > >> As stated, all of the servers are identical in terms of hardware and > >> software and configuration. The only differences in the ntp.conf is that > >> each system is missing the entry for itself. > > >It is possible that there may a problem with this hardware. Does the > >clock always drift in the same direction? Do you see periodic clock > >steps? You may need to adjust the kernel's tick. > > That is precisely what ntp is supposed to do for you. > Unless you are suggesting that the clock drift is greater than 500PPM. He > could look at the drift rate (adjtimex -p and look at the frequency. > The quoted one is in weird units. > It looks line frequency/14555 is PPM > If this is near 500 then you are introuble and have very bad hardware.
I still suspect that you are missing some things I mentioned about the problem. First, the system syncs to ntp just fine as long as I comment the reference clocks (truetime and PPS) out. If I simply list all of the remote ntp servers, it works fine. When the CDMA clock was receiving time, all was well, too. Time is very stable and I see the drift at 93.576 ppm. It's a FreeBSD system, so no adjtimex command. I used ntptime to get the frequency information. Here is a simple table of operation: Refclock refclock refclock not working in ntp.conf in ntp.conf YES syncs syncs NO drifts syncs The only case of failure is when the reference clock is in the ntp.conf file and the reference clock is not providing good time. When I say "not providing time, it is providing time that is pretty close, but it is marked "No Satellite Lock". It maybe that it is, somehow, still syncing to the time from that clock, but it is claiming not to have read the clock at all. I am very suspicious as the offset I was seeing was only about 5 ms last week and is 10 ms today. (I have been running with the reference clock commented out of ntp.conf for that time.) Another thought...could it be PPS that is causing it? After all, the pin on the bulkhead connector is still getting the PPS signal. I am using the kernel PPS implementation, so could that be training the kernel even though ntp is not using it? -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: [EMAIL PROTECTED] Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751 _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
