Re: gpsd Reliable and resilient tcp feed

[Nick Taylor]

Hi

Sorry to top post here but I'm sending from my phone...

Our requirement to use tcp feed is driven by the fact that this is a truck mounted solution.

The trucks are already fitted with various hardware including gps and the clients prefer not to add additional antenna to feed our add on system.

Their system is capable of providing an nmea feed over tcp which is what we are trying to use for these particular clients.

It basically works quite well but as you can understand it's quite an unpredictable environment and we experience loss of tcp connection and thus gps.

We still have option of adding some kind of gps watchdog to reconnect but having this built into gpsd itself would be far cleaner.

We have made some progress with improving reliability but it's a complex beast and I'm sure that a gpsd guru could solve much easier.

Any takers for a contract to help us out?

Thanks and regards

Nick

On 30 Sep 2021 at 18:35, Gary E. Miller <gem@rellim.com> wrote:

Yo Nick!



On Thu, 30 Sep 2021 12:45:02 +0100

Nick Taylor <nicktaylor@dataskill.uk> wrote:



> We need to use tcp feed into gpsd - our customer is providing the

> feed so udp not really an option.



Many other options beyond udp.  How many serial and USB ports does your

GNSS receiver have?



> Requirement is for reliable and resilient tcp feed to gpsd. Currently

> it doesn't do very well if feed gets interrupted - either by restart

> of the feed or if we block the connection for a while with iptables

> to simulate interrupted feed.



Yup.  Nothing new there.  gpsd does not do any reconnect.



> I realise that gpsd is a complex beast and our guy hasn't yet come up  

> with working solution - we keep getting bad side effects like gpsd  

> failing to respond to client connects and broken shm ntp feed



Yup, as I warned you about your code.



> Any gpsd gurus here interested in some contract work - or can anyone  

> point us to someone who could help??



I have been known to accept contracts to add gpsd features.  I might have

already added NTRIP reconnect, except I've never seen NTRIP add any

precision.  So why bother?



Can you demonstarte that your NTRIP feed improves your precision?

RGDS

GARY

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	gem@rellim.com  Tel:+1 541 382 8588



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