[ntp:questions] picking a system peer

Jason Rabel jason at extremeoverclocking.com
Sat Aug 18 02:45:23 UTC 2007


>> http://www.ece.udel.edu/~mills/ntp/html/drivers/driver26.html
>> If you have a Z3801A (or similar), did you add the "mode 1" on the server
>> config line? And did you follow the suggestions for the proper "fudge"
>> factor?
>No. What I posted before is the entire ntp.conf.
><clueless newbie question>
>Where are the docs you're citing located?


The page I linked above is Dr. Mills' site (the creator of NTP). Read the
page for the driver completely..

Specifically the paragraph:
The T is the on-time character, at 980 msec. before the next 1PPS edge. The
# is the timecode format type. We look for format 2. Without any of the CLK
or PPS stuff, then, the receiver buffer timestamp at the <cr> is 24
characters later, which is about 25 msec. at 9600 bps, so the first
approximation for fudge time1 is nominally -0.955 seconds. This number
probably needs adjusting for each machine / OS type, so far: -0.955000 on an
HP 9000 Model 712/80 HP-UX 9.05 -0.953175 on an HP 9000 Model 370 HP-UX 9.10

So.... You will need to modify your ntp.conf to something like:

fudge time1 -0.955

As it says, you will probably have to tweak the fudge number some.

Have you considered adding a PPS signal to the input, since you are running

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