[ntp:questions] offset with ntpdate and ntpq ?

David Woolley david at ex.djwhome.demon.co.uk.invalid
Mon Sep 1 06:39:57 UTC 2008

Uwe Klein wrote:
> You get that kind of (wrong) offset when your machine is sitting at the
> end of an ISDN line that is heavily utilised in one direction only.

Exactly.  If you do this with a modem, root distance goes so high that 
the measurements are rejected, but if you do it with something just that 
little bit faster, you end up with balancing positive and negative 
steps, as people start and finish their browser sessions.

> This can be _partly_ remedied with ( or similar )
>     tinker huffpuff 160000

tinker huffpuff was introduced precisely to cover this situation.

> you will still have the clock going south on occasion.

The best approach, though is to prioritise NTP traffic, but with the 
sort of speed of line for which this happens, you are unlikely to be an 
important enough customer of the ISP for them to do it at their end, 
unless they are enlightened enough to have done it for everyone.

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