On Mon, 10 May 2010 07:58:37 +0100, David J Taylor wrote: > I suspect that depends on the precision required. If you /need/ the > precision which the GPS provides, and an inaccurate time is > unacceptable, then add no other sources. If serving time at a reduced > accuracy is acceptable, add four or five external servers for > redundancy. In addition to redundancy, another advantage might be that > you get a check that you aren't working on the wrong edge of the GPS > pulse, by looking at the output of ntpq -p, and seeing that the offset > of the backup sources is reasonable.
Okay, I think this answers my question. I've been running a Garmin GPS 18 LVC for a few years now... http://www.rjsystems.nl/en/2100-ntpd-garmin-gps-18-lvc-gpsd.php What this page does not say is that my configuration also includes a DFC77 receiver. This long-wave radio time signal receiver is an order of magnitude less precise than the GPS receiver, but it has already proved its value several times in terms of redundancy: twice when the GPS fell from the skylight following a suction-cup failure, and once when gpsd failed to function properly after an update. That's great, but the point is that there's not much else to it. Thanks, Jaap _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
