Re: Ubuntu 18.04.3 build from source testing

[Gary E. Miller]

Yo Steve!

On Mon, 16 Dec 2019 18:26:53 -0600 (CST)
Steve Bourland <address@hidden> wrote:

> Yo Gary!
> 
> Looking fairly good.  Clean install, installed the packages I thought
> I'd need, scons and scons check both passed first go with new
> tarball, and gpspipe -r is reporting:
> 
> $GPRMC,000732.00,A,2926.7338,N,09836.3886,W,0.1346,81.872,171219,4.1,E*41

Some people care about 1 second, so a better confirmation would be nice.

Configure NTPseec to use your gpsd time and look at ntpmon.

Or use cgps against an NTP adjusted time source.

> which looks correct.  There is perhaps a 1 second deviation vs. ntp,
> not sure.  That's where things are off the rails, have installed the
> ntpsec package for Ubuntu server, but gpsd and ntpd don't seem to
> want to talk to each other.

I gotta dozen servers right here using gpsd and ntpd.  Use
ntpshmmon to verify gpsd is sending goot time.  Then look hard at your
ntp.conf.


> Also had this at gpsd startup:
> 
> gpsd:WARN: KPPS:/dev/ttyS0 kernel PPS unavailable, PPS accuracy will 
> suffer

Yup.  Either your kernel has no KPPS support enabled, or you did not compile
it into gpsd, or both.

Send the complete output of your gpsd build and I can check it for you.

> Assume I need to install a PPS package at some point, but that
> shouldn't prevent ntpd and gpsd from talking to each other.

Correct.  It just makes the time more accurate.

> Historically I have had to issue an stty command to set the serial
> line speed to get the PPS signal to hit, but that hasn't helped here.

serial port speed has zero to do with PPS.

You can now use the -s anf -f options to gpsd instead of stty.

>  I'm sort of at a loss, here are the lines from my ntp.conf file:
> # gpsd time source
> server 127.127.28.0
> # With time1 0.420 saw ~-200 msec offset, really just punting here
> fudge 127.127.28.0 time1 0.220 refid NMEA
> server 127.127.28.1 prefer
> fudge 127.127.28.1 time1 0.0002 refid PPS

I assume email munged that?

You need more in you ntp.conf than that for it to work.

Modern config is this way:

refclock shm unit 1 minpoll 4 maxpoll 4 refid PPS flag4 1 prefer
refclock shm unit 0 refid GPS flag4 1 noselect

SHM1 always before SHM0 in the file.  With your other servers (pool, etc.)
between them.

But first, confirm that gpsd is sending with ntpshmmon.

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

            Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

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