OtOpcUa

OPC UA server (.NET 10 AnyCPU) that exposes a fleet of industrial drivers as a single OPC UA address space. Drivers ship in-process for AVEVA System Platform Galaxy (via the sibling mxaccessgw repo), Modbus TCP, Siemens S7, Allen-Bradley CIP (ControlLogix / CompactLogix), Allen-Bradley Legacy (SLC 500 / MicroLogix), Beckhoff TwinCAT (ADS), FANUC FOCAS, OPC UA Client (gateway), and MQTT (broker subscribe; Sparkplug B in progress).

A cross-platform client stack (.NET 10) — shared library, CLI, and Avalonia desktop app — connects to any OPC UA server.

Architecture

                      OPC UA Clients (CLI, Desktop UI, 3rd-party)
                                       |
                                       v
                    +-------------------------------------+
                    |  OtOpcUa.Server (.NET 10 AnyCPU)    |
                    |   address space + capability fan-out|
                    +-------------------------------------+
                    |    |    |    |    |    |    |    |
          Galaxy Modbus S7 AbCip AbLeg TwinCAT FOCAS OpcUaClient MQTT
                |
                v
       mxaccessgw (sibling repo, gRPC)
                |
                v
     MXAccess COM (x86 worker, on AVEVA box)

Galaxy is the only driver with an external runtime: it speaks gRPC to a separately installed mxaccessgw server (sibling repo at c:\Users\dohertj2\Desktop\mxaccessgw\) which owns the MXAccess COM apartment and the x86/STA bitness constraint server-side. Everything in this repo is platform-agnostic .NET 10.

Prerequisites

• .NET 10 SDK (server, drivers, clients all target .NET 10)
• SQL Server reachable for the central config DB
• For Galaxy specifically: a running mxaccessgw deployment — see docs/v2/Galaxy.ParityRig.md
• For historian read-back / alarm history / continuous historization: a running ZB.MOM.WW.HistorianGateway deployment (the sole historian backend; consumed as the ZB.MOM.WW.HistorianGateway.Client gRPC package). It must run RuntimeDb:Enabled=true + RuntimeDb:EventReadsEnabled=true, and the API key must carry historian:read + historian:write + historian:tags:write scopes.

Quick Start

dotnet restore ZB.MOM.WW.OtOpcUa.slnx
dotnet build ZB.MOM.WW.OtOpcUa.slnx
dotnet test ZB.MOM.WW.OtOpcUa.slnx

# Run the server in dev (foreground)
dotnet run --project src/Server/ZB.MOM.WW.OtOpcUa.Host

The server starts on opc.tcp://localhost:4840 with the None security profile. Configure Security.Profiles in src/Server/ZB.MOM.WW.OtOpcUa.Host/appsettings.json to enable Basic256Sha256-Sign or Basic256Sha256-SignAndEncrypt. See docs/security.md.

Install as Windows Services

Production deployment is driven by scripts/install/Install-Services.ps1, which registers the OtOpcUa server service under a chosen service account. Historian support requires a separately deployed ZB.MOM.WW.HistorianGateway and Galaxy support a separately installed mxaccessgw — neither this repo nor the install script provisions them.

.\scripts\install\Install-Services.ps1 `
    -InstallRoot 'C:\Program Files\OtOpcUa' `
    -ServiceAccount 'DOMAIN\svc-otopcua'

The historian backend is the external ZB.MOM.WW.HistorianGateway (not installed by this script). See the script header and docs/ServiceHosting.md for full options.

Client CLI

dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- connect -u opc.tcp://localhost:4840
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- browse  -u opc.tcp://localhost:4840 -r -d 3
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- read    -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode"
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- write   -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode" -v 42
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- subscribe -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode" -i 500

See docs/Client.CLI.md and docs/Client.UI.md.

Documentation

Architecture deep-dives

Topic	Doc
OPC UA server composition, namespace fan-out, Polly invoker	docs/OpcUaServer.md
Address space layout	docs/AddressSpace.md
Read / Write dispatch (driver vs virtual vs scripted-alarm)	docs/ReadWriteOperations.md
Incremental sync (driver-backend rediscovery + config publishes)	docs/IncrementalSync.md
Service hosting (Server + Admin; external HistorianGateway backend)	docs/ServiceHosting.md
Security (transport, LDAP, certificates)	docs/security.md
Redundancy	docs/Redundancy.md
Status dashboard	docs/StatusDashboard.md

Drivers

Topic	Doc
Driver specs (per-driver capability surface, config, addressing)	docs/v2/driver-specs.md
Galaxy driver	docs/drivers/Galaxy.md
Modbus / S7 / AbCip / AbLegacy / TwinCAT / FOCAS / OpcUaClient / MQTT	docs/drivers/
Galaxy parity rig (mxaccessgw setup)	docs/v2/Galaxy.ParityRig.md
Galaxy performance + tracing	docs/v2/Galaxy.Performance.md

Clients

Topic	Doc
Client CLI	docs/Client.CLI.md
Client UI (Avalonia desktop)	docs/Client.UI.md

v1 archive

The original v1 in-process MXAccess docs (Galaxy.Host topology, Configuration env vars, AlarmTracking, DataTypeMapping, HistoricalDataAccess, Subscriptions, etc.) are preserved under docs/v1/ — historical reference only. PR 7.2 retired the v1 architecture on 2026-04-30; current state is documented in the sections above.

License

Internal use only.