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Hi,
I just created a new device template and then a device based on that template. I provisioned a test device, but when I go to the Raw Data view for that device I can see telemetry, properties etc. from a different device (which has a different template). I expected to only see messages for that device. Is the behavior by design?
Regards,
Greg
Hello @Greg McNamara ,
is this related to this Azure IoT Device Node-RED node issue?
Hi, yes I think it might be. I'll see if the node-red developer comes back with any details, but it seems like that node is picking up messages from other flows.
Hello @Greg McNamara ,
Normally, an IoT device registration represents a single physical device.
Therefore, the Node-RED logic is intended to be used with only one Azure Device registration in mind.
Why should you create multiple device connections on multiple flows? Can you tell more about the usecase?
Hi @Sander van de Velde ,
I'm connecting to downstream 3rd party systems via their APIs and databases, and then representing them as IoT devices in Azure. I can't install any code on the 3rd party systems, so the idea was to have a single instance of node-red on a gateway device (e.g. raspberry pi) and connect to (potentially) multiple instances of the 3rd party system that can reside on the same on-premise network. The 3rd party systems are actually machines with their own PC controller, software with an API and database for process results data, so they each have telemetry/properties/commands and it seemed to make sense to represent them as individual devices. I'd prefer not to have a node-red instance or gateway device for each machine if possible.
If it's not possible to connect as multiple devices from a single node-red instance, then my plan B is to move the device representation into the cloud (application level) and only use Azure IoT Hub for the gateway device registration. In that case, using IoT Edge with a module as machine data gateway seems like a better option than node-red. With Edge I also get the module monitoring and deployment functionality, which would be more manual in node-red I guess. I like node-red for its downstream connectivity and protocol options for other devices, Edge is definitely catching up but node-red is still more flexible. Interested in your thoughts.
Regards,
Greg
Hello @Greg McNamara ,
I'm a bit biased because I mainly develop Azure IoT Edge solutions due to the flexibility, remote management, remote configuration, etc.
Eventually, both solutions (Node Red and IoT Edge) are sound solutions. It depends on the requirements and level of programming skills which one is the best fit.
I now better understand the partitioning of the devices and the multiple 'identities' you use.
Please provide this usecase to the Node Red module owner.
Hello @Sander van de Velde ,
Have you had any experience with using an IoT Edge module to act as a device emulator? By this, I mean being able to register devices with IoT Hub (or in this case IoT Central) and then have the module code connect to the Edge Hub as the device and publish device telemetry? In this case I can't run any code on the devices so I have to do everything in the module. At the moment the only IoT Hub device is the IoT Edge device and I lose the ability to separate the telemetry by device. This is a similar concept to the protocol adaptor module, except that I want the downstream devices actually represented as IoT Central devices. An example use case would be visualizing device telemetry in IoT Central, but with telemetry published by a module. Interested in your thoughts on whether this might be possible.
Thanks,
Greg
Hello @Greg McNamara ,
It feels like you are looking for a solution for a simulation of this Identity translation scenario:
Each device is simulated by a module (or a module can simulate multiple modules).
I have not done this myself but it seems you need to provide pre-provisioned device identities to the modules where an implementation of the Azure IoT Device client SDK is running.