[ntp:questions] Compensating for asymmetric delay on a per-peer/server basis?

Rob nomail at example.com
Tue Sep 9 20:20:12 UTC 2014

Rich Wales <richw at richw.org> wrote:
> Is there a way to compensate for asymmetric delay to/from one specific
> peer or server?
> My home LAN is connected to my school's network via a cable modem.
> There appears to be a consistent asymmetry of 2-3 msec between my home
> and the school's network.  I can see this by comparing the time on
> my home server (which is synced to a local GPS) with the time on the
> school servers (which are synced to on-campus GPSes).
> I would like to be able to use the campus network as a backup time
> source for my home LAN, but only if I can somehow compensate for the
> asymmetry introduced by the cable modem infrastructure.
> The asymmetry does not appear to be traffic-dependent; I see pretty
> much the same offset (between 2 and 3 msec) at any time, day or night.
> I'm running NTP version 4.2.6p5 at 1.2349-o.
> Rich Wales
> richw at richw.org

Yes, you can use:

fudge time1 -0.002

or similar.   see the manual.

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