mqtt_connect(&client) does not return any value during operation, and the program is stuck in mqtt_connect(&client) and does not come out

Hi,

There's several configuration(s) and function calls missing from the partial code that you posted, so I am unable to test your scenario. Do you see the same issue with for instance mqtt_simple sample?

Kind regards,

Håkon

Call mt_mqtt_connect() in this function and find that the function has no return value. The program stops in this function. According to the log print information, the program stops in the function err = mqtt_connect(&client).

Tested according to the method you said, and did not solve the problem, indicating that the problem I encountered is different from the problem you mentioned, and it should be a new problem.

First of all, the connection to mqtt is blocked, and I did not reconnect to mqtt because the program is stuck in the mqtt connection and does not return, but once the mqtt connection is successful, I will use mqtt_disconnect() to close the socket after sending the data.I can make sure that the socket is closed every time before connecting mqtt

Hi,

Could you try setting these configurations to see if the scenario improves?

CONFIG_NRF_MODEM_LIB_SENDMSG_BUF_SIZE=2048
CONFIG_NRF_MODEM_LIB_HEAP_SIZE=2048

Kind regards,

Håkon

Hi，

I added the two macros you mentioned and tested them for a day on ncs1.6.0 and mfw_nrf9160_1.2.7, and found that the problem was improved. Some get stuck for 3 and a half minutes and return an error code, and sometimes get stuck for more than ten minutes and return an error code. The error returned is EINVAL. I will test for a few more days to see if the problem is completely solved. If it does solve the problem, I will test again on ncs1.5.1 and mfw_nrf9160_1.2.3 to see if this problem can also be solved. I will reply to the results after the test to you, thank you so much!

Hi，

I tested one more day, unfortunately, the problem reappeared, stuck in mqtt connection with no return value all the time.

Hi,

george.zhou said:

I added the two macros you mentioned and tested them for a day on ncs1.6.0 and mfw_nrf9160_1.2.7, and found that the problem was improved. Some get stuck for 3 and a half minutes and return an error code, and sometimes get stuck for more than ten minutes and return an error code. The error returned is EINVAL.

This is expected behavior if the nRF is unable to connect, due to network connectivity problems.

george.zhou said:

I tested one more day, unfortunately, the problem reappeared, stuck in mqtt connection with no return value all the time.

And this was with which SDK and modem fw?

The connect() call never returned?

Kind regards,

Håkon

Hi,

george.zhou said:

I added the two macros you mentioned and tested them for a day on ncs1.6.0 and mfw_nrf9160_1.2.7, and found that the problem was improved. Some get stuck for 3 and a half minutes and return an error code, and sometimes get stuck for more than ten minutes and return an error code. The error returned is EINVAL.

This is expected behavior if the nRF is unable to connect, due to network connectivity problems.

george.zhou said:

I tested one more day, unfortunately, the problem reappeared, stuck in mqtt connection with no return value all the time.

And this was with which SDK and modem fw?

The connect() call never returned?

Kind regards,

Håkon

Hi，

I tested on ncs1.6.0 and mfw_nrf9160_1.2.7. No return value for more than ten hours after the problem occurred

Hi, is there any progress on this issue?

Hi,

If NCS v1.6.0, with these additional configurations 

CONFIG_NRF_MODEM_LIB_SENDMSG_BUF_SIZE=2048
CONFIG_NRF_MODEM_LIB_HEAP_SIZE=2048

did not help the scenario, can you please try a newer version of NCS to see if the issue is triggered there? This is to debug to see if the application behavior itself can have an impact on the scenario.

Kind regards,

Håkon