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From: Mills@udel.edu
Newsgroups: comp.protocols.time.ntp
Subject: Re:  NTP experiment - large drifts on unsynced systems
Message-ID: <9103071505.aa13612@huey.udel.edu>
Date: 7 Mar 91 20:05:36 GMT
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Paul,

I have no idea why your VAXen wobbled, unless there are hidden
gotchas in their timekeeping code. I ordinarily expect our
chimers to stay within a few milliseconds per day after
being synchronized for a few days. This assumes the machines
are maintained in a normal room with temperature changes limited
do a degree C or so. Now, if you were running Suns, I wouldn't
be surprised.

For sanity check, once you lose outside chime, your machines
may form a daisy-chained loop which slowly (one step per minute)
counts to 15, so that all machines eventually drop off and run
independently. Wehn this occurs, each machine should continue
to get updates from NTP to maintain the frequency adjustment.
It's just possible that the software port neglected that little
chore. If so, the wobble you are seeing is due to the intrinsic
hardware that comes with the machine. 

Dave