Log a Warning if messages are deleted from the StoreAndForward/offline cache (because of TTL)
Currently there is no way to figure out that messages were deleted because of the Time To Live/TTL StoreAndForward configuration. There should be a warning in the Logs if this happens to hint the deletion of messages that were not sent to IoT Hub. Ideally there is a configurable second warning before this happens (e.g. 10 minutes before messages get deleted because of TTL).
In addition it would be great to add more control to the StoreAndForward/Caching/Queuing functionality of messaging - refer to ideas https://feedback.azure.com/forums/907045-azure-iot-edge/suggestions/33534802-more-options-or-configuration-parameters-of-stor and https://feedback.azure.com/forums/907045-azure-iot-edge/suggestions/36632884-low-bandwidth-partially-connected-message-deliv
Check out the latest version of IoT Edge, 1.0.10. We’ve instrumented the runtime to produce metrics about the runtime’s performance. One of them is edgehub_messages_dropped_total.