[ntp:questions] Re: NTP sync problems

Terje Mathisen terje.mathisen at hda.hydro.com
Thu Dec 16 16:25:09 UTC 2004

David L. Mills wrote:

> Guys,
> There might be some misconception here. The mitigation algorithm 
> establishes a bound on the offset of any server with respect to 
> roundtrip delay and dispersion. This is a matter of physics and theory. 
> When multiple servers are involved, the algorithm computes an 
> intersection interval within which the server clocks can be considered 
> valid. A possibly correct time must be contained in this intersection. 
> If the intersection is empty, a correct time cannot be established. This 
> is independent of the stratum.

Sure, this is obviously right.

My suggestion was based on the idea that if the secondary server would 
always use the primary as its own preferred source, then it would have 
to have more or less the same time, right?

Actually finding two servers with no intersection interval pretty much 
proves that either one or both of them are misconfigured, and without a 
proper UTC reference.


- <Terje.Mathisen at hda.hydro.com>
"almost all programming can be viewed as an exercise in caching"

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