Issue with Downlinks from Azure IoT Hub to Device via TTN

Hello TTN Community,

I am currently experiencing an issue with Cloud-to-Device (C2D) messaging from Azure IoT Hub to a LoRa node device connected through The Things Network (TTN). I would greatly appreciate your assistance in resolving this issue. Below are the details of the problem:


  • Azure IoT Hub: I am using Azure IoT Hub to send Cloud-to-Device messages to my LoRa node device, which is connected to TTN.
  • TTN Integration: The LoRa node device is connected to TTN, and I have set up an integration to forward messages from TTN to my azure iot hub.

Current Setup:

  • Device: I am using an ESP32 with an SX1278 LoRa module to send sensor data to TTN.
  • TTN Integration: The device data is successfully forwarded to TTN, and I can receive the data in my Azure IoT Hub.


  • Cloud-to-Device messages from Azure IoT Hub do not appear to be reaching my LoRa node device connected to TTN.
  • I have confirmed that the device is properly registered and activated on TTN, and messages from the device to the azure iot hub are working as expected.

I kindly request your expertise in troubleshooting and providing guidance on how to send data from Azure IoT Hub to my LoRa node device connected to TTN. I am currently able to send data from the device to the Azure IoT Hub successfully, but I am seeking assistance in setting up the communication in the reverse direction, from the Azure IoT Hub to the LoRa device.

If you have encountered a similar challenge or if you have any insights or suggestions on how to establish this bidirectional communication, please share them with me. Your guidance and support would be immensely valuable in helping me achieve this objective.

Thank you in advance for your time and assistance.

Best regards,
Abhithlal C

Have you tried entering a downlink in the TTN console to check if that reaches the LoRa device? If not, please do so and report the results.

where in the documentation do they mention how to schedule downlinks from azure to ttn

how are you attempting to schedule these message from azure

I was referring to this document LINK

I am capable of arranging the downlink message from TTN, and it can be successfully received on my device.

Is it possible to send downlink message from azure iot hub to device?
If yes, then how can I?

you will need to read the azure side of the documentation

here is a few recourse to reed i have not read them just googled for 2min to find this

1 Like

Thank you for your response, and I’m sorry for the delay in getting back to you. After going through the resources, unfortunately, I couldn’t solve my problem. It appears that scheduling a downlink from the device twin in Azure IoT Hub by modifying the desired property is possible. However, I also faced challenges in creating or deleting devices from Azure IoT Hub. I suspect that both issues may have the same underlying cause.