On Wed, Jan 05, 2011 at 09:23:59AM +0100, Terje Mathisen wrote: > Two servers which don't overlap, and a third which overlaps (partly) > both of them: > > <----> <----> server A and B > <---> server C > > In this particular situation C must be a survivor, but since it > overlaps both A and B with an identical amount, there is no way to > determine if (A^C) or (B^C) is the best interval to pick.
The select algorithm doesn't care how much they overlap. Recent ntp-dev versions work as described on the select.html web page, so the intersection interval will be equal to C and all three sources will pass. Older versions worked also with centers of the intervals and as the centers of A and B are lying outside the intersection interval, C would be the only truechimer. I'd be curious to hear why that approach was dropped. -- Miroslav Lichvar _______________________________________________ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
