Re: NTPsec reports excessive jitter from GPSD/KPPS SHM

[Gary E. Miller]

Yo Paul!

On Tue, 10 Mar 2020 11:52:45 -0700
Paul Theodoropoulos via <address@hidden> wrote:

> On 3/10/20 11:40, Gary E. Miller wrote:
> > Yo Nick!
> >
> > On Tue, 10 Mar 2020 18:15:27 +0000
> > "Nick Burkitt" <address@hidden> wrote:
> >  
> >> I think it's time to stick a fork in this one.  
> > Almost.  A few things still hanging.
> >
> > You still have this near the top of your ntp.conf:
> >
> >      # GPS Serial data reference (NTP0)
> >      refclock shm unit 0 refid GPS noselect
> >
> > It should be after all your other time sources.  
> Question - if the GPS refclock is noselect, shouldn't that mitigate
> the necessity to have it at the bottom of the list?

Yeah, mostly, but many people do not want the GPS refclock to be
noselect.

For example, if you have a power outage, and on reboot your net is
still down, then the PPS can not work without another chimer with valid
seconds.  So your NTP can not get a time.  The GPS can provide the base
seconds, so avoiding that trap.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        address@hidden  Tel:+1 541 382 8588

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