Re: [gpsd-dev] Clarifications needed for the time-service HOWTO

[Harlan Stenn]

"Eric S. Raymond" writes:
> Harlan Stenn <address@hidden>:
> > If "at least two others" means "the one already on this machine and at
> > least 2 outside sources" that's great.  ntpd needs a majority clique to
> > sync, and if there are only 2 time sources and they disagree then ntpd
> > won't know who to listen to.
> > 
> > H
> 
> Gary has upgraded that recommended number to 4.

The problem with 4 is that one can get 2 cliques of 2 members.

The problem with 3 is that if one goes away you have 2.

5 is great until one goes away and you risk having 2 groups of 2 again.

So the best answer I know is "do what you want and be sure to have
adequate monitoring."