sfptpd provides a simple clustering algorithm to select
between sync instances using a discriminator mode. In this mode a
passive sync instance (for example NTP) is designated as the discriminator between
multiple active sync instances (such as PTP). Any wildly divergent time sources are
excluded from the sync instance selection.
Note: While similar to the
sfptpd Best Master
Clock (BMC) Discriminator feature this operates between sync instances (on separate PTP
domains and/or interfaces) rather than within a PTP domain and is a preferable solution
because full clock reconstruction is continuously performed for each candidate
source.For example the following configuration prefers sync instances that are
within 100 ms (100000000 ns) of an NTP reference, the sync instance for which is named
ntp1:
[general]
clustering discriminator ntp1 100000000 1See Configuration Options for a complete description of the
clustering option.
Future releases might provide further modes of clustering beyond a discriminator.