NB-IoT BC66 - SSL (via MQTT), PSK (via LWM2M) does not work

[Chris5]

Hi all,
I connected the Olimex NB-IOT (w/ Antenna)with USB(UART) and tried to access mqtt.googleapis.com endpoint for MQTT and leshan.eclipseprojects.io endpoint for L2M2M. All works fine until I change the seclevel (SSL) or secure mode (PSK for LWM2M), would be great, if someone can point me to a working example.

AT+QSSLCFG=3,5,"seclevel",2
AT+QSSLCFG=3,5,"cacert",1906
AT+QSSLCFG=3,5,"clientcert",1101
AT+QSSLCFG=3,5,"clientkey",1706

Still opening a connection does not work.

AT+QSSLOPEN=3,5,"mqtt.googleapis.com",8883
OK

+QSSLOPEN,3,5,-9

-9 = "Other Error" (According to the specs)


I used MQTT.fx to verify that the certificates actually work. They do. Also going back to "seclevel",1 with only server certificate verification is does not change the situation.

I uploaded the most recent firmware from ftp://staging.olimex.com . Did not change the situation.

I then tried to shift to LWM2M. Similar situation. Shifting from no security mode to PSK (Private Security Key)it does not connect and shows error "other error". I reached out to the Quectel forum with no solution and Quectel Tech Support is referring to Olimex Support.

It would be great, if someone could help me out here. Hopefully, it's just a misconfiguration on my part.

Thanks
Chris

[LubOlimex]

Did you use AT + QLWCONFIG at any point?

Check here for LwM2M example, chapter 3:

https://docs.iotcreators.com/docs/quectel-bc66