Re: [TCP/MQTT] Connection issue

Guillaume Paquet

Hello Zephyr Community,

I found where something is wrong.
Indeed in net_context_get function, I saw that I reached CONFIG_NET_MAX_CONTEXTS (equal to 10 in my prj.conf).
For your information, I use UBLOX sara r4 driver (on zephyr 1.14.1 as I mentionned in my previous mail) and I wonder if contexts are well managed in this revision, especially when socket is closed ? 

Thanks in advance for your help

Best Regards,


De : devel@... <devel@...> de la part de Guillaume Paquet via Lists.Zephyrproject.Org <>
Envoyé : mercredi 11 décembre 2019 16:24
À : Guillaume Paquet <guillaume.paquet@...>; devel@... <devel@...>
Cc : devel@... <devel@...>
Objet : Re: [Zephyr-devel] [TCP/MQTT] Connection issue

And just to add some precision, I work on zephyr 1.14.1.






De : devel@... <devel@...> De la part de Guillaume Paquet via Lists.Zephyrproject.Org
Envoyé : mercredi 11 décembre 2019 13:50
À : devel@...
Cc : devel@...
Objet : [Zephyr-devel] [TCP/MQTT] Connection issue


Hello Zephyr community,


I contact you because I have an issue when I run mqtt_publisher example


I have the following issue when I have multiple mqtt connection/disconnection (through tcp transport_connect function)

[try_to_connect:233] mqtt_connect: -2 <ERROR>


I have this issue after 10 connection/disconnection. The eleventh one is always failing.

As I said you I saw that this is failing when I try to run mqtt_transport_connect(client); in client_connect.


My configuration is the following one :

  • MQTT (not secured)
  • TCP/IPv4
  • Broker on external server (not any issue on this one)


If you have any idea to help me


Thanks in advance


Best Regards



Guillaume  PAQUET – IoT Engineer

guillaume.paquet@...  -  02 40 18 50 91

1 Avenue Professeur Jean Rouxel – ZAC Fleuriaye

44470 CARQUEFOU – FRANCE                


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