64d8838e18
The 'All 19 PRs merged' banner contradicted the warning paragraph in
the same block and overstated reality against the source tree. Audit
of the lmxopcua + mxaccessgw repos on 2026-05-01 found:
- 17 of 19 PRs merged. Four merged PRs ship inert scaffolds:
- A.2: MxAccessAlarmEventSink.Attach is a no-op.
- A.3 / A.4: NotWiredAlarmRpcDispatcher returns OK-with-diagnostic
for AcknowledgeAlarm and an empty stream for QueryActiveAlarms.
- C.1: SdkAlarmHistorianWriteBackend.WriteBatchAsync returns
RetryPlease for every event with a placeholder log.
- The architectural decision the warning paragraph asks the operator
to make was already resolved 2026-04-30. MxAccessAlarmEventSink.cs
in mxaccessgw records that aaAlarmManagedClient.AlarmClient is x86
net48 (same bitness as the worker), and pins the discovered API
surface (RegisterConsumer / Subscribe / GetStatistics /
GetAlarmExtendedRec / AlarmAckByGUID). What remains is wiring PRs
in the worker, not architectural choice.
- D.1 smoke artifact (docs/plans/artifacts/d1-rollout-YYYY-MM-DD.md)
not yet captured; directory does not exist.
Banner rewritten to split functional-end-to-end vs merged-but-inert
PRs explicitly so future readers don't have to reconcile the doc
against the source tree themselves.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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, and OPC UA Client (gateway).
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
|
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
mxaccessgwdeployment — see docs/v2/Galaxy.ParityRig.md - For Wonderware Historian read-back: optional
OtOpcUaWonderwareHistoriansidecar — see docs/ServiceHosting.md
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/ZB.MOM.WW.OtOpcUa.Server
The server starts on opc.tcp://localhost:4840 with the None security profile. Configure Security.Profiles in src/ZB.MOM.WW.OtOpcUa.Server/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 (and optionally the OtOpcUaWonderwareHistorian sidecar) under a chosen service account. Galaxy support requires a separately installed mxaccessgw — neither this repo nor the install script provisions it.
.\scripts\install\Install-Services.ps1 `
-InstallRoot 'C:\Program Files\OtOpcUa' `
-ServiceAccount 'DOMAIN\svc-otopcua'
Add -InstallWonderwareHistorian for the historian sidecar. See the script header and docs/ServiceHosting.md for full options.
Client CLI
dotnet run --project src/ZB.MOM.WW.OtOpcUa.Client.CLI -- connect -u opc.tcp://localhost:4840
dotnet run --project src/ZB.MOM.WW.OtOpcUa.Client.CLI -- browse -u opc.tcp://localhost:4840 -r -d 3
dotnet run --project src/ZB.MOM.WW.OtOpcUa.Client.CLI -- read -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode"
dotnet run --project src/ZB.MOM.WW.OtOpcUa.Client.CLI -- write -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode" -v 42
dotnet run --project src/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 + optional historian sidecar) | 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 | 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.