Re: [chrony-users] Not getting time from gpsd

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Awesome man I'm glad it's working for you! I use buildroot for most everything and then I can compile everything much easier all at once

On Aug 8, 2016 1:22 PM, "Chris Greenman" <chris.m.greenman@xxxxxxxxx> wrote:
UGH!!!    I really wish distros would provide software that is more up to date.    Looks like it might have been gpsd.

On a whim I decided to scrap the repo provided gpsd AND chrony and compiled everything myself.  it now appears as if everything is working.  

chrony sources output:

210 Number of sources = 1
MS Name/IP address         Stratum Poll Reach LastRx Last sample               
#* GPS                           0   4   377    17   +296us[ +347us] +/-  200ms

I am perfectly happy with 200ms error in time.   That more than suits my needs..

Sorry for wasting everyone's time.    I was trying to save time and frustration by using the repo supplied (and you would think tested) binaries.   It would have been a lot quicker and less frustrating to just compile.  lol.

On Mon, Aug 8, 2016 at 11:50 AM, Chris Greenman <chris.m.greenman@xxxxxxxxx> wrote:
Ok,  Here are the latest strace files.  It looks like the chrony in the Jessie repos does not have debug compiled in.  I downloaded the latest source and compiled.  The trace is using that binary not the distro supplied (Ver. 1.30).  I should note that I already tried the fresh compiled version before and got the same results as the distro version.

On Mon, Aug 8, 2016 at 9:19 AM, Miroslav Lichvar <mlichvar@xxxxxxxxxx> wrote:
On Mon, Aug 08, 2016 at 09:05:03AM -0400, Chris Greenman wrote:
> I didn't think the -F option was correct but it didn't seem to work without
> it either.  I was just hunting and pecking.  My gps does not (directly)
> provide PPS.  It's a ublox 6 so I could probably wire it in but to be
> honest, I don't need that much precision.  For my needs NTP is accurate
> enough but it's not always available which is why I want time from GPS.

Note that GPS without PPS is typically less stable than NTP over
internet. Binary mode may work better than NMEA.

> As
> for the dependencies and starting order, that's easy to fix.  Right now
> gpsd is starting from init.d and chrony is starting from systemd.  I can
> just remove the rc#.d links and write a new .service file for gpsd with
> "After = chrony.service" and "Wanted by =".  Then verify the
> chrony service file jives with the one for gpsd.

With SHM refclock that shouldn't be necessary. Only for SOCK chronyd
needs to be started first.

> The last gps strace I posted was with the -D 8 option specified.   I did
> not, however, specify -f to strace so it is not following after it forks.

The -N option disables forking. Another useful option is -n, which
tells gpsd to not wait for clients, so SHM is always updated.

> As soon as I get some play time today I'll run some new traces.  Is
> attaching the best way to send the files or is there a bit bucket somewhere
> I should use?

I think it's ok to post here if it's not too large (e.g. > 100KB). Or
you can compress it first.

Miroslav Lichvar

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