[ntp:questions] GPS and the December 5/6 Solar Flare

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Sat Apr 7 20:19:45 UTC 2007


>I have the GPS receiver (many), I have the Rubidium standard (many),
>I have a PC with FreeBSD (or any other good OS needed) and, of course,
>we all have NTPD.
>My questions was how can I make this system to depend as little as
>possible on the GPS signal.
>
>I exposed a solution - by the two "prefer" kewords. This is a good
>solution as the drift after
>four days was negligible (<1E-6).

Using prefer with the PPS is a hack.  The real problem is to get
the which-second info.  Getting it from yourself (prefer-ing the
local refclock) may work if your local time is set correctly,
somehow, but it's not a clean long term solution.  You can't
get started if you don't have a GPS or external system to
get close-enough and you can't detect or recover if somehow
your system gets off by a second.  (Think leap seconds with
software bugs.)

-- 
These are my opinions, not necessarily my employer's.  I hate spam.




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