CCS/CC3200: CC3200 : MQTT Reconnection

Hi,

Can you describe how your application is currently handling the MQTT client setup / connection after the Wi-Fi disconnect and reconnect sequence? Is it the same as in the example?

Generally speaking, there is no reconnection flow that should be specific to our device. It should be based on the requirements of the server/options used by the client. For example, the device should be able to simply reconnect the same way as it initially connected and resubscribe to topics when using a "clean session" if the MQTT server supports client takeover.

If you see that this sequence is not working in the demo under some circumstances, perhaps there is an issue in the code with recreating the client context and reconnecting.

Best Regards,
Ben M

Hi Benjamin,

Whenever device connects to the internet, MQTT functionality should start. 

while(1){

if(Connect_To_Wifi() == true)

Start_MQTT();

}

I have used the example code for implementation, I do not need queue part of the code, so I have removed that code. Initially the MQTT code is working as per the expectation. But in case of MQTT re-connection ( AFTER WiFi re-connection), device is unable to connect to the broker. If I use function "sl_ExtLib_MqttClientDisconnect" in label at the end of MQTTClient function, the code will stop after disconnection and nothing happens after that. 

I tried using  "sl_ExtLib_MqttClientExit()" in "sl_MqttDisconnect" callback, but at re-connection case the code stops at connection part. Similarly, fucntion "sl_ExtLib_MqttClientCtxDelete()" causes similar issues(there are some MUTEX lock issues with sl_ExtLib_MqttClientCtxDelete function). 

What approach can be used to resolve the issue?

thanks, 

Trupti.

Hi Trupti,

Trupti Jadhav said:

Similarly, fucntion "sl_ExtLib_MqttClientCtxDelete()" causes similar issues(there are some MUTEX lock issues with sl_ExtLib_MqttClientCtxDelete function).

Please elaborate on this. What mutex lock issues? This is how the current mqtt_client example currently handles the disconnection/reconnection and it works well from my testing.

Are you not using an RTOS at all?

Thanks,

Ben M