lmxopcua/service_info.md

Service Update Summary

Updated service instance: C:\publish\lmxopcua\instance1

Update time: 2026-03-25 12:54-12:55 America/New_York

Backup created before deploy: C:\publish\lmxopcua\backups\20260325-125444

Configuration preserved:

• C:\publish\lmxopcua\instance1\appsettings.json was not overwritten.

Deployed binary:

• C:\publish\lmxopcua\instance1\ZB.MOM.WW.LmxOpcUa.Host.exe
• Last write time: 2026-03-25 12:53:58
• Size: 143360

Windows service:

• Name: LmxOpcUa
• Display name: LMX OPC UA Server
• Account: LocalSystem
• Status after update: Running
• Process ID after restart: 29236

Restart evidence:

• Service log file: C:\publish\lmxopcua\instance1\logs\lmxopcua-20260325_004.log
• Last startup line: 2026-03-25 12:55:08.619 -04:00 [INF] The LmxOpcUa service was started.

CLI Verification

Endpoint from deployed config:

• opc.tcp://localhost:4840/LmxOpcUa

CLI used:

• C:\Users\dohertj2\Desktop\lmxopcua\tools\opcuacli-dotnet\bin\Debug\net10.0\opcuacli-dotnet.exe

Commands run:

opcuacli-dotnet.exe connect -u opc.tcp://localhost:4840/LmxOpcUa
opcuacli-dotnet.exe read -u opc.tcp://localhost:4840/LmxOpcUa -n 'ns=1;s=MESReceiver_001.MoveInPartNumbers'
opcuacli-dotnet.exe read -u opc.tcp://localhost:4840/LmxOpcUa -n 'ns=1;s=MESReceiver_001.MoveInPartNumbers[]'

Observed results:

• connect: succeeded, server reported as LmxOpcUa.
• read ns=1;s=MESReceiver_001.MoveInPartNumbers: succeeded with good status 0x00000000.
• read ns=1;s=MESReceiver_001.MoveInPartNumbers[]: failed with BadNodeIdUnknown (0x80340000).

---

Instance 2 (Redundant Secondary)

Deployed: 2026-03-28

Deployment path: C:\publish\lmxopcua\instance2

Configuration:

• OpcUa.Port: 4841
• OpcUa.ServerName: LmxOpcUa2
• OpcUa.ApplicationUri: urn:localhost:LmxOpcUa:instance2
• Dashboard.Port: 8082
• MxAccess.ClientName: LmxOpcUa2
• Redundancy.Enabled: true
• Redundancy.Mode: Warm
• Redundancy.Role: Secondary
• Redundancy.ServerUris: ["urn:localhost:LmxOpcUa:instance1", "urn:localhost:LmxOpcUa:instance2"]

Windows service:

• Name: LmxOpcUa2
• Display name: LMX OPC UA Server (Instance 2)
• Account: LocalSystem
• Endpoint: opc.tcp://localhost:4841/LmxOpcUa

Instance 1 redundancy update (same date):

• OpcUa.ApplicationUri: urn:localhost:LmxOpcUa:instance1
• Redundancy.Enabled: true
• Redundancy.Mode: Warm
• Redundancy.Role: Primary
• Redundancy.ServerUris: ["urn:localhost:LmxOpcUa:instance1", "urn:localhost:LmxOpcUa:instance2"]

CLI verification:

opcuacli-dotnet.exe redundancy -u opc.tcp://localhost:4840/LmxOpcUa
  → Redundancy Mode: Warm, Service Level: 200, Application URI: urn:localhost:LmxOpcUa:instance1

opcuacli-dotnet.exe redundancy -u opc.tcp://localhost:4841/LmxOpcUa
  → Redundancy Mode: Warm, Service Level: 150, Application URI: urn:localhost:LmxOpcUa:instance2

Both instances report the same ServerUriArray and expose the same Galaxy namespace (urn:ZB:LmxOpcUa).

LDAP Authentication Update

Updated: 2026-03-28

Both instances updated to use LDAP authentication via GLAuth.

Configuration changes (both instances):

• Authentication.AllowAnonymous: true (anonymous can browse/read)
• Authentication.AnonymousCanWrite: false (anonymous writes blocked)
• Authentication.Ldap.Enabled: true
• Authentication.Ldap.Host: localhost
• Authentication.Ldap.Port: 3893
• Authentication.Ldap.BaseDN: dc=lmxopcua,dc=local

LDAP server: GLAuth v2.4.0 at C:\publish\glauth\ (Windows service: GLAuth)

Permission verification (instance1, port 4840):

anonymous read    → allowed
anonymous write   → denied  (BadUserAccessDenied)
readonly  read    → allowed
readonly  write   → denied  (BadUserAccessDenied)
readwrite write   → allowed
admin     write   → allowed
alarmack  write   → denied  (BadUserAccessDenied)
bad password      → denied  (connection rejected)

Alarm Notifier Chain Update

Updated: 2026-03-28

Both instances updated with alarm event propagation up the notifier chain.

Code changes:

• Alarm events now walk up the parent chain (ReportEventUpNotifierChain), reporting to every ancestor node
• EventNotifier = SubscribeToEvents is set on all ancestors of alarm-containing nodes (EnableEventNotifierUpChain)
• Removed separate Server.ReportEvent call (no longer needed — the walk reaches the root)

No configuration changes required — alarm tracking was already enabled (AlarmTrackingEnabled: true).

Verification (instance1, port 4840):

alarms --node TestArea --refresh:
  TestMachine_001.TestAlarm001 → visible (Severity=500, Retain=True)
  TestMachine_001.TestAlarm002 → visible (Severity=500, Retain=True)
  TestMachine_001.TestAlarm003 → visible (Severity=500, Retain=True)
  TestMachine_002.TestAlarm001 → visible (Severity=500, Retain=True)
  TestMachine_002.TestAlarm003 → visible (Severity=500, Retain=True)

alarms --node DEV --refresh:
  Same 5 alarms visible at DEV (grandparent) level

Auth Consolidation Update

Updated: 2026-03-28

Both instances updated to consolidate LDAP roles into OPC UA session roles (RoleBasedIdentity.GrantedRoleIds).

Code changes:

• LDAP groups now map to custom OPC UA role NodeIds in urn:zbmom:lmxopcua:roles namespace
• Roles stored on session identity via GrantedRoleIds — no username-to-role side cache
• Permission checks use GrantedRoleIds.Contains() instead of username extraction
• AnonymousCanWrite behavior is consistent regardless of LDAP state
• Galaxy namespace moved from ns=2 to ns=3 (roles namespace is ns=2)

No configuration changes required.

Verification (instance1, port 4840):

anonymous read      → allowed
anonymous write     → denied  (BadUserAccessDenied, AnonymousCanWrite=false)
readonly  write     → denied  (BadUserAccessDenied)
readwrite write     → allowed
admin     write     → allowed
alarmack  write     → denied  (BadUserAccessDenied)
bad password        → rejected (connection failed)

Granular Write Roles Update

Updated: 2026-03-28

Both instances updated with granular write roles replacing the single ReadWrite role.

Code changes:

• ReadWrite role replaced by WriteOperate, WriteTune, WriteConfigure
• Write permission checks now consider the Galaxy security classification of the target attribute
• SecurityClassification stored in TagMetadata for per-node lookup at write time

GLAuth changes:

• New groups: WriteOperate (5502), WriteTune (5504), WriteConfigure (5505)
• New users: writeop, writetune, writeconfig
• admin user added to all groups (5502, 5503, 5504, 5505)

Config changes (both instances):

• Authentication.Ldap.ReadWriteGroup replaced by WriteOperateGroup, WriteTuneGroup, WriteConfigureGroup

Verification (instance1, port 4840, Operate-classified attributes):

anonymous read        → allowed
anonymous write       → denied  (AnonymousCanWrite=false)
readonly  write       → denied  (no write role)
writeop   write       → allowed (WriteOperate matches Operate classification)
writetune write       → denied  (WriteTune doesn't match Operate)
writeconfig write     → denied  (WriteConfigure doesn't match Operate)
admin     write       → allowed (has all write roles)

Historian SDK Migration

Updated: 2026-04-06

Both instances updated to use the Wonderware Historian SDK (aahClientManaged.dll) instead of direct SQL queries for historical data access.

Code changes:

• HistorianDataSource rewritten from SqlConnection/SqlDataReader to ArchestrA.HistorianAccess SDK
• Persistent connection with lazy connect and auto-reconnect on failure
• HistorianConfiguration.ConnectionString replaced with ServerName, IntegratedSecurity, UserName, Password, Port
• HistorianDataSource now implements IDisposable, disposed on service shutdown
• ConfigurationValidator validates Historian SDK settings at startup

SDK DLLs deployed to both instances:

• aahClientManaged.dll (primary SDK, v2.0.0.0)
• aahClient.dll, aahClientCommon.dll (dependencies)
• Historian.CBE.dll, Historian.DPAPI.dll, ArchestrA.CloudHistorian.Contract.dll

Configuration changes (both instances):

• Historian.ConnectionString removed
• Historian.ServerName: "localhost"
• Historian.IntegratedSecurity: true
• Historian.Port: 32568
• Historian.Enabled: true (unchanged)

Verification (instance1 startup log):

Historian.Enabled=true, ServerName=localhost, IntegratedSecurity=true, Port=32568
Historian.CommandTimeoutSeconds=30, MaxValuesPerRead=10000
=== Configuration Valid ===
LmxOpcUa service started successfully

HistoryServerCapabilities and Continuation Points

Updated: 2026-04-06

Both instances updated with OPC UA Part 11 spec compliance improvements.

Code changes:

• HistoryServerCapabilities node populated under ServerCapabilities with all boolean capability properties
• AggregateFunctions folder populated with references to 7 supported aggregate functions
• HistoryContinuationPointManager added — stores remaining data when results exceed NumValuesPerNode
• HistoryReadRawModified and HistoryReadProcessed now return ContinuationPoint in HistoryReadResult for partial reads
• Follow-up requests with ContinuationPoint resume from stored state; invalid/expired points return BadContinuationPointInvalid

No configuration changes required.

Verification (instance1 startup log):

HistoryServerCapabilities configured with 7 aggregate functions
LmxOpcUa service started successfully

Remaining Historian Gaps Fix

Updated: 2026-04-06

Both instances updated with remaining OPC UA Part 11 spec compliance fixes.

Code changes:

• Gap 4: HistoryReadRawModified returns BadHistoryOperationUnsupported when IsReadModified=true
• Gap 5: HistoryReadAtTime override added with ReadAtTimeAsync using SDK HistorianRetrievalMode.Interpolated
• Gap 8: HistoricalDataConfigurationState child nodes added to historized variables (Stepped=false, Definition="Wonderware Historian")
• Gap 10: ReturnBounds parameter handled — boundary DataValue entries with BadBoundNotFound inserted at StartTime/EndTime
• Gap 11: StandardDeviation aggregate added to client enum, mapper, CLI (aliases: stddev/stdev), and UI dropdown

No configuration changes required.

Historical Event Access

Updated: 2026-04-06

Both instances updated with OPC UA historical event access (Gap 7).

Code changes:

• HistorianDataSource.ReadEventsAsync queries Historian event store via separate HistorianConnectionType.Event connection
• LmxNodeManager.HistoryReadEvents override maps HistorianEvent records to OPC UA HistoryEventFieldList entries
• AccessHistoryEventsCapability set to true when AlarmTrackingEnabled is true
• Event fields: EventId, EventType, SourceNode, SourceName, Time, ReceiveTime, Message, Severity

No configuration changes required. All historian gaps (1-11) are now resolved.

Data Access Gaps Fix

Updated: 2026-04-06

Both instances updated with OPC UA DA spec compliance fixes.

Code changes:

• ConfigureServerCapabilities() populates ServerCapabilities node: ServerProfileArray, LocaleIdArray, MinSupportedSampleRate, continuation point limits, array/string limits, and 12 OperationLimits values
• Server_ServerDiagnostics_EnabledFlag set to true — SDK auto-tracks session/subscription counts
• OnModifyMonitoredItemsComplete override logs monitored item modifications

No configuration changes required. All DA gaps (1-8) resolved.

Alarms & Conditions Gaps Fix

Updated: 2026-04-06

Both instances updated with OPC UA Part 9 alarm spec compliance fixes.

Code changes:

• Wired OnConfirm, OnAddComment, OnEnableDisable, OnShelve, OnTimedUnshelve handlers on each AlarmConditionState
• Shelving: SetShelvingState() manages TimedShelve, OneShotShelve, Unshelve state machine
• ReportAlarmEvent now populates LocalTime (timezone offset + DST) and Quality event fields
• Flaky Monitor_ProbeDataChange_PreventsStaleReconnect test fixed (increased stale threshold from 2s to 5s)

No configuration changes required. All A&C gaps (1-10) resolved.

Security Gaps Fix

Updated: 2026-04-06

Both instances updated with OPC UA Part 2/4/7 security spec compliance fixes.

Code changes:

• SecurityProfileResolver: Added 4 modern AES profiles (Aes128_Sha256_RsaOaep-Sign/SignAndEncrypt, Aes256_Sha256_RsaPss-Sign/SignAndEncrypt)
• OnImpersonateUser: Added X509IdentityToken handling with CN extraction and role assignment
• BuildUserTokenPolicies: Advertises UserTokenType.Certificate when non-None security profiles are configured
• OnCertificateValidation: Enhanced logging with certificate thumbprint, subject, and expiry
• Authentication audit logging: AUDIT: prefixed log entries for success/failure with session ID and roles

No configuration changes required. All security gaps (1-10) resolved.

Historian Plugin Runtime Load + Dashboard Health

Updated: 2026-04-12 18:47-18:49 America/New_York

Both instances updated to the latest build. Brings in the runtime-loaded Historian plugin (Historian/ subfolder next to the Host) and the status dashboard health surface for historian plugin + alarm-tracking misconfiguration.

Backups created before deploy:

• C:\publish\lmxopcua\backups\20260412-184713-instance1
• C:\publish\lmxopcua\backups\20260412-184713-instance2

Configuration preserved:

• C:\publish\lmxopcua\instance1\appsettings.json was not overwritten.
• C:\publish\lmxopcua\instance2\appsettings.json was not overwritten.

Layout change:

• Flat historian interop DLLs removed from each instance root (aahClient*.dll, ArchestrA.CloudHistorian.Contract.dll, Historian.CBE.dll, Historian.DPAPI.dll).
• Historian plugin + interop DLLs now live under <instance>\Historian\ (including ZB.MOM.WW.LmxOpcUa.Historian.Aveva.dll), loaded by HistorianPluginLoader.

Deployed binary (both instances):

• ZB.MOM.WW.LmxOpcUa.Host.exe
• Last write time: 2026-04-12 18:46:22 -04:00
• Size: 7938048

Windows services:

• LmxOpcUa — Running, PID 40176
• LmxOpcUa2 — Running, PID 34400

Restart evidence (instance1 logs/lmxopcua-20260412.log):

2026-04-12 18:48:02.968 -04:00 [INF] Historian.Enabled=true, ServerName=localhost, IntegratedSecurity=true, Port=32568
2026-04-12 18:48:02.971 -04:00 [INF] === Configuration Valid ===
2026-04-12 18:48:09.658 -04:00 [INF] Historian plugin loaded from C:\publish\lmxopcua\instance1\Historian\ZB.MOM.WW.LmxOpcUa.Historian.Aveva.dll
2026-04-12 18:48:13.691 -04:00 [INF] LmxOpcUa service started successfully

Restart evidence (instance2 logs/lmxopcua-20260412.log):

2026-04-12 18:49:08.152 -04:00 [INF] Historian.Enabled=true, ServerName=localhost, IntegratedSecurity=true, Port=32568
2026-04-12 18:49:08.155 -04:00 [INF] === Configuration Valid ===
2026-04-12 18:49:14.744 -04:00 [INF] Historian plugin loaded from C:\publish\lmxopcua\instance2\Historian\ZB.MOM.WW.LmxOpcUa.Historian.Aveva.dll
2026-04-12 18:49:18.777 -04:00 [INF] LmxOpcUa service started successfully

CLI verification (via dotnet run --project src/ZB.MOM.WW.LmxOpcUa.Client.CLI):

connect    opc.tcp://localhost:4840/LmxOpcUa → Server: LmxOpcUa
connect    opc.tcp://localhost:4841/LmxOpcUa → Server: LmxOpcUa2
redundancy opc.tcp://localhost:4840/LmxOpcUa → Warm, ServiceLevel=200, urn:localhost:LmxOpcUa:instance1
redundancy opc.tcp://localhost:4841/LmxOpcUa → Warm, ServiceLevel=150, urn:localhost:LmxOpcUa:instance2

Both instances report the same ServerUriArray and the primary advertises the higher ServiceLevel, matching the prior redundancy baseline.

Endpoints Panel on Dashboard

Updated: 2026-04-13 08:46-08:50 America/New_York

Both instances updated with a new Endpoints panel on the status dashboard surfacing the opc.tcp base addresses, active OPC UA security profiles (mode + policy name + full URI), and user token policies.

Code changes:

• StatusData.cs — added EndpointsInfo / SecurityProfileInfo DTOs on StatusData.
• OpcUaServerHost.cs — added BaseAddresses, SecurityPolicies, UserTokenPolicies runtime accessors reading ApplicationConfiguration.ServerConfiguration live state.
• StatusReportService.cs — builds EndpointsInfo from the host and renders a new panel with a graceful empty state when the server is not started.

No configuration changes required.

Verification (instance1 @ http://localhost:8085/):

Base Addresses: opc.tcp://localhost:4840/LmxOpcUa
Security Profiles: None / None / http://opcfoundation.org/UA/SecurityPolicy#None
User Token Policies: Anonymous, UserName

Verification (instance2 @ http://localhost:8086/):

Base Addresses: opc.tcp://localhost:4841/LmxOpcUa
Security Profiles: None / None / http://opcfoundation.org/UA/SecurityPolicy#None
User Token Policies: Anonymous, UserName

Template-Based Alarm Object Filter

Updated: 2026-04-13 09:39-09:43 America/New_York

Both instances updated with a new configurable alarm object filter. When OpcUa.AlarmFilter.ObjectFilters is non-empty, only Galaxy objects whose template derivation chain matches a pattern (and their containment-tree descendants) contribute AlarmConditionState nodes. When the list is empty, the current unfiltered behavior is preserved (backward-compatible default).

Backups created before deploy:

• C:\publish\lmxopcua\backups\20260413-093900-instance1
• C:\publish\lmxopcua\backups\20260413-093900-instance2

Deployed binary (both instances):

• ZB.MOM.WW.LmxOpcUa.Host.exe
• Last write time: 2026-04-13 09:38:46 -04:00
• Size: 7951360

Windows services:

• LmxOpcUa — Running, PID 40900
• LmxOpcUa2 — Running, PID 29936

Code changes:

• gr/queries/hierarchy.sql — added recursive CTE on gobject.derived_from_gobject_id and a new template_chain column (pipe-delimited, innermost template first).
• Domain/GalaxyObjectInfo.cs — added TemplateChain: List<string> populated from the new SQL column.
• GalaxyRepositoryService.cs — reads the new column and splits into TemplateChain.
• Configuration/AlarmFilterConfiguration.cs (new) — List<string> ObjectFilters; entries may themselves be comma-separated. Attached to OpcUaConfiguration.AlarmFilter.
• Configuration/ConfigurationValidator.cs — logs the effective filter and warns if patterns are configured while AlarmTrackingEnabled == false.
• Domain/AlarmObjectFilter.cs (new) — compiles wildcard patterns (* only) to case-insensitive regexes with Galaxy $ prefix normalized on both sides; walks the hierarchy top-down with cycle defense; returns a HashSet<int> of included gobject IDs plus UnmatchedPatterns for startup warnings.
• OpcUa/LmxNodeManager.cs — constructor accepts the filter; the two alarm-creation loops (BuildAddressSpace full build and the subtree rebuild path) both call ResolveAlarmFilterIncludedIds(sorted) and skip any object not in the resolved set. New public properties expose filter state to the dashboard: AlarmFilterEnabled, AlarmFilterPatternCount, AlarmFilterIncludedObjectCount.
• OpcUa/OpcUaServerHost.cs, OpcUa/LmxOpcUaServer.cs, OpcUaService.cs, OpcUaServiceBuilder.cs — plumbing to construct and thread the filter from appsettings.json down to the node manager.
• Status/StatusData.cs + Status/StatusReportService.cs — AlarmStatusInfo gains FilterEnabled, FilterPatternCount, FilterIncludedObjectCount; a filter summary line renders in the Alarms panel when the filter is active.

Tests:

• 36 new unit tests in tests/.../Domain/AlarmObjectFilterTests.cs covering pattern parsing, wildcard semantics, regex escaping, Galaxy $ normalization, template-chain matching, subtree propagation, set semantics, orphan/cycle defense, and UnmatchedPatterns tracking.
• 5 new integration tests in tests/.../Integration/AlarmObjectFilterIntegrationTests.cs spinning up a real LmxNodeManager via OpcUaServerFixture and asserting AlarmConditionCount/AlarmFilterIncludedObjectCount under various filters.
• 1 new Status test verifying JSON exposes the filter counters.
• Full suite: 446/446 tests passing (no regressions).

Configuration change: both instances have OpcUa.AlarmFilter.ObjectFilters: [] (filter disabled, unfiltered alarm tracking preserved).

Live verification against instance1 Galaxy (filter temporarily set to "TestMachine"):

2026-04-13 09:41:31 [INF] OpcUa.AlarmTrackingEnabled=true, AlarmFilter.ObjectFilters=[TestMachine]
2026-04-13 09:41:42 [INF] Alarm filter: 42 of 49 objects included (1 pattern(s))
Dashboard Alarms panel: Tracking: True | Conditions: 60 | Active: 4
                        Filter: 1 pattern(s), 42 object(s) included

Final configuration restored to empty filter. Dashboard confirms unfiltered behavior on both endpoints:

instance1 @ http://localhost:8085/ → Conditions: 60 | Active: 4 (no filter line)
instance2 @ http://localhost:8086/ → Conditions: 60 | Active: 4 (no filter line)

Filter syntax quick reference (documented in AlarmFilterConfiguration.cs XML-doc):

• * is the only wildcard (glob-style; zero or more characters).
• Matching is case-insensitive and ignores the Galaxy leading $ template prefix on both the pattern and the stored chain entry, so operators write TestMachine* not $TestMachine*.
• Each entry may contain comma-separated patterns for convenience (e.g., "TestMachine*, Pump_*").
• Empty list → filter disabled → current unfiltered behavior.
• Match semantics: an object is included when any template in its derivation chain matches any pattern, and the inclusion propagates to all descendants in the containment hierarchy. Each object is evaluated once regardless of how many patterns or ancestors match.

Historian Runtime Health Surface

Updated: 2026-04-13 10:44-10:52 America/New_York

Both instances updated with runtime historian query instrumentation so the status dashboard can detect silent query degradation that the load-time PluginStatus cannot catch.

Backups:

• C:\publish\lmxopcua\backups\20260413-104406-instance1
• C:\publish\lmxopcua\backups\20260413-104406-instance2

Code changes:

• Host/Historian/HistorianHealthSnapshot.cs (new) — DTO with TotalQueries, TotalSuccesses, TotalFailures, ConsecutiveFailures, LastSuccessTime, LastFailureTime, LastError, ProcessConnectionOpen, EventConnectionOpen.
• Host/Historian/IHistorianDataSource.cs — added GetHealthSnapshot() interface method.
• Historian.Aveva/HistorianDataSource.cs — added _healthLock-guarded counters, RecordSuccess() / RecordFailure(path) helpers called at every terminal site in all four read methods (raw, aggregate, at-time, events). Error messages carry a raw: / aggregate: / at-time: / events: prefix so operators can tell which SDK call is broken.
• Host/OpcUa/LmxNodeManager.cs — exposes HistorianHealth property that proxies to IHistorianDataSource.GetHealthSnapshot().
• Host/Status/StatusData.cs — added 9 new fields on HistorianStatusInfo.
• Host/Status/StatusReportService.cs — BuildHistorianStatusInfo() populates the new fields from the node manager; panel color gradient: green → yellow (1-4 consecutive failures) → red (≥5 consecutive or plugin unloaded). Renders Queries: N (Success: X, Failure: Y) | Consecutive Failures: Z, Process Conn: open/closed | Event Conn: open/closed, plus Last Success: / Last Failure: / Last Error: lines when applicable.
• Host/Status/HealthCheckService.cs — new Rule 2b2: Degraded when ConsecutiveFailures >= 3. Threshold chosen to avoid flagging single transient blips.

Tests:

• 5 new unit tests in HistorianDataSourceLifecycleTests covering fresh zero-state, single failure, multi-failure consecutive increment, cross-read-path counting, and error-message-carries-path.
• Full suite: 16/16 plugin tests, 447/447 host tests passing.

Live verification on instance1:

Before any query:
  Queries: 0 (Success: 0, Failure: 0) | Process Conn: closed | Event Conn: closed
After TestMachine_001.TestHistoryValue raw read:
  Queries: 1 (Success: 1, Failure: 0) | Process Conn: open
  Last Success: 2026-04-13T14:45:18Z
After aggregate hourly-average over 24h:
  Queries: 2 (Success: 2, Failure: 0)
After historyread against an unknown node id (bad tag):
  Queries: 2 (counter unchanged — rejected at node-lookup before reaching the plugin; correct)

JSON endpoint /api/status carries all 9 new fields with correct types. Both instances deployed; instance1 LmxOpcUa PID 33824, instance2 LmxOpcUa2 PID 30200.

Historian Read-Only Cluster Support

Updated: 2026-04-13 11:25-12:00 America/New_York

Both instances updated with Wonderware Historian read-only cluster failover. Operators can supply an ordered list of historian cluster nodes; the plugin iterates them on each fresh connect and benches failed nodes for a configurable cooldown window. Single-node deployments are preserved via the existing ServerName field.

Backups:

• C:\publish\lmxopcua\backups\20260413-112519-instance1
• C:\publish\lmxopcua\backups\20260413-112519-instance2

Code changes:

• Host/Configuration/HistorianConfiguration.cs — added ServerNames: List<string> (defaults to []) and FailureCooldownSeconds: int (defaults to 60). ServerName preserved as fallback when ServerNames is empty.
• Host/Historian/HistorianClusterNodeState.cs (new) — per-node DTO: Name, IsHealthy, CooldownUntil, FailureCount, LastError, LastFailureTime.
• Host/Historian/HistorianHealthSnapshot.cs — extended with ActiveProcessNode, ActiveEventNode, NodeCount, HealthyNodeCount, Nodes: List<HistorianClusterNodeState>.
• Historian.Aveva/HistorianClusterEndpointPicker.cs (new, internal) — pure picker with injected clock, thread-safe via lock, BFS-style GetHealthyNodes() / MarkFailed() / MarkHealthy() / SnapshotNodeStates(). Nodes iterate in configuration order; failed nodes skip until cooldown elapses; the cumulative FailureCount and LastError are retained across recovery for operator diagnostics.
• Historian.Aveva/HistorianDataSource.cs — new ConnectToAnyHealthyNode(type) method iterates picker candidates, clones HistorianConfiguration per attempt with the candidate as ServerName, and returns the first successful (Connection, Node) tuple. EnsureConnected and EnsureEventConnected both call it. HandleConnectionError and HandleEventConnectionError now mark the active node failed in the picker before nulling. _activeProcessNode / _activeEventNode track the live node for the dashboard. Both silos (process + event) share a single picker instance so a node failure on one immediately benches it for the other.
• Host/Status/StatusData.cs — added NodeCount, HealthyNodeCount, ActiveProcessNode, ActiveEventNode, Nodes to HistorianStatusInfo.
• Host/Status/StatusReportService.cs — Historian panel renders Process Conn: open (<node>) badges and a cluster table (when NodeCount > 1) showing each node's state, cooldown expiry, failure count, and last error. Single-node deployments render a compact Node: <hostname> line.
• Host/Status/HealthCheckService.cs — new Rule 2b3: Degraded when NodeCount > 1 && HealthyNodeCount < NodeCount. Lets operators alert on a partially-failed cluster even while queries are still succeeding via the remaining nodes.
• Host/Configuration/ConfigurationValidator.cs — logs the effective node list and FailureCooldownSeconds at startup, validates that FailureCooldownSeconds >= 0, warns when ServerName is set alongside a non-empty ServerNames.

Tests:

• HistorianClusterEndpointPickerTests.cs — 19 unit tests covering config parsing, ordered iteration, cooldown expiry, zero-cooldown mode, mark-healthy clears, cumulative failure counting, unknown-node safety, concurrent writers (thread-safety smoke test).
• HistorianClusterFailoverTests.cs — 6 integration tests driving HistorianDataSource via a scripted FakeHistorianConnectionFactory: first-node-fails-picks-second, all-nodes-fail, second-call-skips-cooled-down-node, single-node-legacy-behavior, picker-order-respected, shared-picker-across-silos.
• Full plugin suite: 41/41 tests passing. Host suite: 446/447 (1 pre-existing flaky MxAccess monitor test passes on retry).

Live verification on instance1 (cluster = ["does-not-exist-historian.invalid", "localhost"], FailureCooldownSeconds=30):

Failover cycle 1 (fresh picker state, both nodes healthy):

2026-04-13 11:27:25.381 [WRN] Historian node does-not-exist-historian.invalid failed during connect attempt; trying next candidate
2026-04-13 11:27:25.910 [INF] Historian SDK connection opened to localhost:32568

• historyread returned 1 value successfully (Queries: 1 (Success: 1, Failure: 0)).
• Dashboard: panel yellow, Cluster: 1 of 2 nodes healthy, bad node cooldown until 11:27:55Z, Process Conn: open (localhost).

Cooldown expiry:

• At 11:29 UTC, the cooldown window had elapsed. Panel back to green, both nodes healthy, but does-not-exist-historian.invalid retains FailureCount=1 and LastError as history.

Failover cycle 2 (service restart to drop persistent connection):

2026-04-13 14:00:39.352 [WRN] Historian node does-not-exist-historian.invalid failed during connect attempt; trying next candidate
2026-04-13 14:00:39.885 [INF] Historian SDK connection opened to localhost:32568

• historyread returned 1 value successfully on the second restart cycle — proves the picker re-admits a cooled-down node and the whole failover cycle repeats cleanly.

Single-node restoration:

• Changed instance1 back to "ServerNames": [], restarted. Dashboard renders Node: localhost (no cluster table), panel green, backward compat verified.

Final configuration: both instances running with empty ServerNames (single-node mode). LmxOpcUa PID 31064, LmxOpcUa2 PID 15012.

Operator configuration shape:

"Historian": {
  "Enabled": true,
  "ServerName": "localhost",                // ignored when ServerNames is non-empty
  "ServerNames": ["historian-a", "historian-b"],
  "FailureCooldownSeconds": 60,
  ...
}

Notes

The service deployment and restart succeeded. The live CLI checks confirm the endpoint is reachable and that the array node identifier has changed to the bracketless form. The array value on the live service still prints as blank even though the status is good, so if this environment should have populated MoveInPartNumbers, the runtime data path still needs follow-up investigation.