NRF52840 + OpenThread + Azure IoT Hub / MQTT Sample

[SebastianCorin]

Hi!

I am looking for a NRF52840+OpenThread+Azure IoT Hub SDK solution. Here is what I did so far. Nothing helped:

1. Thead CLI Example on NRF52840 + Border Router on PI with RCP NRF52840 is working. I can ping ipv6 in mesh and outside mesh. I can ping ipv4 outside mesh
2. I merged the code of nRF9160: Azure IoT Hub — nRF Connect SDK 2.2.99 documentation (nordicsemi.com) into the Thread CLI example, created and added certificates and ended up with:

*** Booting Zephyr OS build v3.2.99-ncs1 ***
Azure IoT Hub sample started
Azure IoT Hub library initialized
AZURE_IOT_HUB_EVT_CONNECTING
E: getaddrinfo() failed, error -11
E: mqtt_helper_connect failed, error: 11
Connection request sent to IoT Hub

I am aware of the following tickets but nothing what was described helped. There is no complete description included:

• (+) Azure IoT Hub Library with OpenThread - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com)
• (+) Error -22 in mqtt_connect() - nRF52840dk with Azure IoT Hub using OpenThread and TCP - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com)

My ask is a working sample with Azure IoT Hub and Openthread / MQTT and Openthread.

I added my github repo to make the code available for testing: sebastianspross/nrf52840_ot_azure (github.com)

Really appriciate your help!

Thanks

Sebastian

[Susheel Nuguru]

My ask is a working sample with Azure IoT Hub and Openthread / MQTT and Openthread.

We unfortunately do not have a working sample supporting this combo. Do not see in the roadmap for this either. We do not have the resources to test and debug features/combos that are not supported yet.

[SebastianCorin]

okay, thanks for the quick reply.

Is there a working example for NRF52840 + Openthread + Plain MQTT? I see projects on github but never a complete working sample.

I heard about ipv6 and native mqtt support for the Azure IoT Hub which might changes the situation.

What would you recommend to go for in the meantime? Coap Client on NRF52840 and a Coap bridge in the cloud is currently my next idea. Do you have another idea?

[SebastianCorin]

I am still trying to find a solution. Currently I am working on the zephyr Azure MQTT sample. I run there in the same problem. The dns resolve of the ipv4 of the Azure IoT Hub fails. I found the following commit which enables resolve4 which looks promising: [dns-client] add support for NAT64 during address resolution by abtink · Pull Request #6414 · openthread/openthread (github.com)

But how can I set 

OPENTHREAD_CONFIG_DNS_CLIENT_NAT64_ENABLE=y

?

*edit: I ported the Azure MQTT sample from zephyr into the openthread cli sample from nrfconnect

[Susheel Nuguru]

Sorry for the late reply Sebastian, I do not have any other idea, but will double check with the networking team to get their insights aswell. I will come back to you as soon as they give me any response.

[Susheel Nuguru]

OPENTHREAD_CONFIG_DNS_CLIENT_NAT64_ENABLE=y should be default set to y when CONFIG_OPENTHREAD_DNS_CLIENT is enabled. If this is not the case, then there seems to be some conflicts in your project configuration and the build system should have some warning when compiling. If that is not the case, then I can report this issue to the developers.