[ntp:questions] Magice Server Numbers: 4,5,7,9

Harlan Stenn stenn at ntp.org
Fri Sep 16 07:25:13 UTC 2011

Doug wrote:
>  From time to time people mention that the magic number of servers is
> 4,5,7 and nine. However I can not find a reference or explanation for
> the magical properties. Can anyone explain the background/basis in
> general? And specifically how is five or seven preferable to six?

You want an odd number in case yuo have 2 "cliques" that each have
a different idea of what the correct time is.

ntpd wants a "majority" clique to sync to.


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