[ntp:questions] Slow convergence of NTP with GPS/PPS

David Woolley david at ex.djwhome.demon.co.uk.invalid
Tue Sep 30 21:46:28 UTC 2008

Kevin Oberman wrote:

> Most important is to start ntpd at boot time with the -g option so that
> it will immediately set the time. Then adjust your ntp.conf to set the
> maxpoll and minpoll to 4 for your reference clock. 
> "minpoll 4 maxpoll 4"

Most reference clocks ignore maxpoll, and I think quite a lot ignore 

> This will get the time synced to close to correct, hopefully a few
> microseconds, within a couple of minutes, depending on your hardware.

It will get you with a maximum error of about 128ms.  You can do 
somewhat better if you ensure that you start off more than 128ms out, as 
that will force an initial step.

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