nRF9160 MQTT connection failure

[khodidas]

Hi,

We are using nRF9160 ncs version 1.0.0. 

I have two queries.

We are making connection with AWS server. In the backend we have telenor server. 

We make MQTT connection, publish data and disconnect from server.

Connection interval is 5 minutes. 

We have observed that after 7-8 hours of successful connection (more than 100 times ) it gets stuck in

"connect" function inside "mqtt_client_tls_connect" function. It never comes out of "connect" function. 

Second query is we are using "lte_lc_psm_req" function to put the device in PSM mode to save power.

During first MQTT connection with AWS server device takes more than 10 minutes ( There are multiple failures in MQTT connection during this time )

Initially we get error -111 and then we get error -60. 

After 10 to 15 minutes, connection with  server is established and thereafter we don't have any issue in connection.

Can you help me in resolving this issue ?

Regards,

Smitesh Mali

[Simonr]

Hi

I've asked my colleagues about your matter, and they suggest this might be a mismatch somewhere. Could you try running a checkout in the repo, and a west update, as well as reinstalling the newest modem firmware onto the nRF9160.

Also, it seems I misunderstood the AT+CPSMS? command, this will give you the requested values, and not the actual set values from the network. If you call AT+CEREG=5 followed by AT+CEREG? you should get the actual PSM-interval from the network.

Best regards,

Simon

[khodidas]

Hi,

I got "+CEREG: 5,1,"7A45","011DA405",7,,,"00000001","10111110"<CR>".

So settings received from network is

CONFIG_LTE_PSM_REQ_RPTAU="10111110" and CONFIG_LTE_PSM_REQ_RAT = 00000001

Our setting is below 

CONFIG_LTE_PSM_REQ_RPTAU="00000011"

CONFIG_LTE_PSM_REQ_RAT="00000000"

So TAU value as per my calculation is 30 minutes in both "10111110" and "00000011" settings. 

So I don't think it should make difference in terms of timing is concerned.

Regards,

Smitesh Mali