This module provides edge services to the cloud-based OPC Twin micro-service.

The module supports network discovery of OPC UA servers on the edge network. Endpoint discovery can be configured remotely using the OPC Registry service REST API. After each discovery probe, discovered endpoints are added as device identities in Azure IoT Hub’s device registry by the OPC Onboarding Agent service.

The OPC Twin micro-service REST API can then be used to access a server endpoint through its corresponding IoT Hub Device identity and the OPC UA client in the OPC Twin module to browse the address space and read, write, as well as call methods and – if supported - access a server’s OPC UA Historical Data Access (HDA) interface.

The module integrates with the OPC Publisher module in the same IoT Edge hosting context and allows you to set up OPC UA data subscriptions in the module through the OPC Twin micro-service API. The resulting monitored item notifications are then continuously published to the Azure IoTHub service through the OPC Publisher where the data can be routed for further processing and analytics.

Minimum hardware requirements: Linux (x64), Linux (arm32), 2 cores, 4GB RAM, 1GB disk space.