On Mon, Jan 06, 2025 at 06:12:53PM +0800, Yuezhen LUAN wrote: > But some of the chrony clients also mark B as falseticker, some marked B as > combined, some marked B as selectable but not combined, and all chrony > clients select C as current time source. > > Offset between B and C are small enough(currently 200us~300us). According > to selection algorithm, I think B shouldn't be falseticker? 'chronyc > selectdata -a -v' shows like this: > > [image: chronyc_selectdata.png]
That output shows that the sources A and B don't have any overlap in their intervals and both overlap with C. This is a corner case in the chrony selection algorithm that IIRC is handled differently than in ntpd. That overlap between A and C is only about 30 microseconds. A small difference in the network delay, timestamping, etc could cause that overlap to disappear, which would make make B lose the falseticker status. That will also happen if A drifts further away from B and C. -- Miroslav Lichvar -- To unsubscribe email chrony-users-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-users-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.
