[ntp:questions] Isolated Network Drift Problem

Maarten Wiltink maarten at kittensandcats.net
Wed Nov 26 13:03:36 UTC 2008

"Hal Murray" <hal-usenet at ip-64-139-1-69.sjc.megapath.net> wrote in message
news:Cf2dncgZtOTSkbDUnZ2dnUVZ_g2dnZ2d at megapath.net...

>>> By staggered do you mean that none may live in the same stratum?
>> Staggered means all at different strata.
>> Correctly staggered adds the constraint that they must differ by at
>> least two from each other, as well.
> Why do they need to differ by steps of 2?

Because a server running off the local clock will report the server's
stratum as one higher then the clock's. So a backup server with a
local clock only one stratum higher than the primary's will have two
sources at the same level to choose from: its own local clock, and
the primary server.

It has been argued that it might, or even would, pick the wrong source,
but that's really beside the point. If the primary server is available
at all, there must be no choice.

Maarten Wiltink

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