[ntp:questions] Using both Server and Peer in ntp.conf

David Woolley david at djwhome.demon.co.uk
Thu Feb 8 22:41:07 UTC 2007

In article <n23s94-2n5.ln1 at robert.houseofmax.de>,
Uwe Klein <uwe_klein_habertwedt at t-online.de> wrote:

> quality and/or stratum

> with/without the local clock
> being used as (additional) server

This should make no difference to the true quality.  It will result in
the server reporting a falsely optimistic root dispersion and failing to
drop back to stratum 16; the latter when 8 consecutive polls have failed
for all servers.  (The continuing increase in root dispersion is where
I think w32time, Win 2003 SP1, actually gets it right; ntpd assumes an
external synchronisation source in its generation of error estimates.)

> over time?

Depends on how stable the system was when it lost the synchronisation 
source.  If it was dead on frequency and in an air conditioned room, 
one could reasonably hope for 30 seconds a year (the best way of getting
this is to calibrate the frequency over several days, rather than using
ntpd to measure it).

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