Re: [gpsd-users] gpsd to gpsd connection not working reliably

[Eric S. Raymond]

Florian Petry <address@hidden>:
> for testing purposes inside a laboratory I want to connect several
> testing machines to one “GPS server” that has a USB GPS receiver
> connected.  I wanted to use the possibility of setting
> gpsd://<IP-ADDRESS>:<PORT> as an input device. But this does not
> reliably work.

You may hace a subtle comfiguration problem.  Or, because the JSON
passthrough c ode has been tested very little, it may have a genuine
bug.

The logs you attached look like normal srartups.  There is nothing obviously
wrong with them

> Here is my setup:
> 
> “GPS server”:
> 
>                 sudo /usr/sbin/gpsd -b -S 3333 -D2 -N -G -F 
> /var/run/gpsd.sock -P /var/run/gpsd.pid /dev/ttyUSB0
> 
> 
> “Client” gpsd:
> 
>                 sudo /usr/sbin/gpsd -G -N -D9 -F /var/run/gpsd.sock -P 
> /var/run/gpsd.pid gpsd://172.19.1.201:3333

That looks correct, assuming that 172.19.1.201 is the IP address of the
machine the server gpsd instances are running on.

> I see the the detached message in the server when closing the gpsd
> on the client. And sometimes I even get data when using gpsmon to
> verify.  Gpsmon called with the IP and Port of the “gps server”
> always works on the client.
>
> How can I reliably connect two instances of gpsd? Is this setup
> multiclient capable?

I am going to test a multi-daemon setup here to verify that it works.  But
in order to try to get you to a solution as quickly as possible I'm going to
ask a more basic question:

Why run the "client" instance at all? Why not have your applications open
TCP/IP or UDP connections to the server gpsd instance?  That case is
very well tested.
-- 
                <a href="http://www.catb.org/~esr/";>Eric S. Raymond</a>