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UDT Tags at Edge with Transmission set to Convert UDTs = False

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You cannot have UDTs definitions with the same name and different tag members within the system.

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MQTT Engine uses the MD5 sum of the UDT to detect differences and will ignore any new UDT definitions received that share the same name as the first recorded UDT definition.

If a collision is detected, a warning will be logged and you can see the detail by setting the com.cirruslink.mqtt.engine.gateway.sparkplug.SparkplugBPayloadHandler to TRACE.

This detail will show the UDT definition at MQTT Engine and also the UDT definition published in the NBIRTH message. The offending edge node can be identified from the NBIRTH message.

Changes made at an edge device to UDT definition member tags are not propagated through the system. You will see that any tag instances of that UDT at the edge device will reflect the changes, but the recorded definition for the UDT at engine will not change nor will tag instances for other edge devices using that definition.

UDT Collision Detection