Dave, Thanks for the quick response, but I guess I failed to make one point clear.
EndRun supplies only the hardware. It is the Ct which as only a serial interface which is plugged into a standard COM port on the server. They don't provide any software at all. The clock just provides the time string every second (with an offset of about 10 ms. and jitter in the area of 3-5 ms.) and a very accurate PPS which allows us sync within about three usec. (The clock spec is better than ten usec, but three seems the norm.) I am running 4.2.0-a using the stock TrueTime and PPS drivers. The FreeBSD kernel has PPS support included, so any filtering in the TrueTime driver should be of little or no impact. I am assuming than as long as I am using PPS and training the TrueTime source, a minpoll of 4 is reasonable and I just wanted to make sure that I am not wrong in doing this. -- 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 > From: "David L. Mills" <[EMAIL PROTECTED]> > Date: Wed, 07 May 2008 21:38:40 +0000 > Sender: [EMAIL PROTECTED] > > > Keven, > > The TrueTime driver that lives here supports all known TrueTime > receivers, including GPS, WWVB and GOES. I strongly suspect one or > another of those receivers would not work if the poll interval was > tinkered. EndRun apparently has cloned most or all that driver and may > have modified it. If they recommend minpoll 4, run that end. > > Dave > > Kevin Oberman wrote: > >>From: "David L. Mills" <[EMAIL PROTECTED]> > >>Date: Wed, 07 May 2008 19:51:20 +0000 > >>Sender: [EMAIL PROTECTED] > >> > >> > >>Heiko, > >> > >>Be careful when making generalizations about refclocks. Some, including > >>the Spectracom, Austron, Traconex, TrueTime and others using the median > >>filter will not workproperly at other than default poll. Same for the > >>modem and audio drivers. > > > > > > I assume that this is driver, not device specific. > > > > server 127.127.5.1 prefer minpoll 4 maxpoll 4 > > fudge 127.127.5.1 refid CDMA > > fudge 127.127.5.1 time1 .010 > > server 127.127.22.1 minpoll 4 maxpoll 4 > > fudge 127.127.22.1 flag3 1 > > > > What about the PPS driver when used with one of these? I use EndRun CDMA > > clocks emulating TrueTime with PPS and EndRun recommends a MINPOLL and > > MAXPOLL of 4. Is that bad advice in such a configuration? If it is > > significant, I use FreeBSD on all of my ntp servers. > > _______________________________________________ > questions mailing list > [email protected] > https://lists.ntp.org/mailman/listinfo/questions >
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