Correct Answer: DeviceNotFound means the sending device is not registered in IoT Hub; MessageSizeExceeded means the message payload exceeds 256 KB
DeviceNotFound indicates the device ID in the message is not registered in the IoT Hub device registry — the device needs to be registered or the ID is incorrect. MessageSizeExceed...
Correct Answer
DeviceNotFound means the sending device is not registered in IoT Hub; MessageSizeExceeded means the message payload exceeds 256 KB
Why This Answer Is Correct
DeviceNotFound indicates the device ID in the message is not registered in the IoT Hub device registry — the device needs to be registered or the ID is incorrect. MessageSizeExceeded indicates the device is sending a payload larger than the 256 KB D2C message limit — the device must split or compress its data.
This question evaluates your knowledge of IoT Monitoring — a core concept tested in Microsoft Certified: Azure IoT Developer Specialty (AZ-220). Understanding IoT Monitoring is essential for designing scalable, secure, and cost-effective cloud architectures. Mastery of this topic will help you answer scenario-based questions confidently on exam day.
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