feat: wire all health metrics and add instance counts to dashboard

Wired ISiteHealthCollector calls for script errors (ScriptExecutionActor),
alarm eval errors (AlarmActor), dead letters (DeadLetterMonitorActor), and
S&F buffer depth placeholder. Added instance count tracking (deployed/
enabled/disabled) to SiteHealthReport via DeploymentManagerActor. Updated
Health Dashboard UI to show instance counts per site. All metrics flow
through the existing health report pipeline via ClusterClient.

src/ScadaLink.CentralUI/Components/Pages/Monitoring/Health.razor

@@ -100,6 +100,23 @@
                                 }
                             </div>
 
+                            @* Instances *@
+                            <div class="col-md-4">
+                                <h6 class="text-muted small mb-2">Instances</h6>
+                                <div class="d-flex justify-content-between mb-1">
+                                    <span class="small">Deployed</span>
+                                    <span>@report.DeployedInstanceCount</span>
+                                </div>
+                                <div class="d-flex justify-content-between mb-1">
+                                    <span class="small">Enabled</span>
+                                    <span class="text-success">@report.EnabledInstanceCount</span>
+                                </div>
+                                <div class="d-flex justify-content-between mb-1">
+                                    <span class="small">Disabled</span>
+                                    <span class="text-warning">@report.DisabledInstanceCount</span>
+                                </div>
+                            </div>
+
                             @* Error Counts *@
                             <div class="col-md-4">
                                 <h6 class="text-muted mb-2">Error Counts</h6>

src/ScadaLink.Commons/Messages/Health/SiteHealthReport.cs

@@ -11,4 +11,7 @@ public record SiteHealthReport(
     int ScriptErrorCount,
     int AlarmEvaluationErrorCount,
     IReadOnlyDictionary<string, int> StoreAndForwardBufferDepths,
-    int DeadLetterCount);
+    int DeadLetterCount,
+    int DeployedInstanceCount,
+    int EnabledInstanceCount,
+    int DisabledInstanceCount);

src/ScadaLink.HealthMonitoring/HealthReportSender.cs

@@ -49,6 +49,10 @@ public class HealthReportSender : BackgroundService
         {
             try
             {
+                // TODO: Wire S&F buffer depths when StoreAndForward service is available in DI
+                // e.g., var depths = await _bufferDepthProvider.GetDepthsAsync();
+                //        _collector.SetStoreAndForwardDepths(depths);
+
                 var seq = Interlocked.Increment(ref _sequenceNumber);
                 var report = _collector.CollectReport(_siteId);
 

src/ScadaLink.HealthMonitoring/ISiteHealthCollector.cs

@@ -15,5 +15,7 @@ public interface ISiteHealthCollector
     void UpdateConnectionHealth(string connectionName, ConnectionHealth health);
     void RemoveConnection(string connectionName);
     void UpdateTagResolution(string connectionName, int totalSubscribed, int successfullyResolved);
+    void SetStoreAndForwardDepths(IReadOnlyDictionary<string, int> depths);
+    void SetInstanceCounts(int deployed, int enabled, int disabled);
     SiteHealthReport CollectReport(string siteId);
 }

src/ScadaLink.HealthMonitoring/SiteHealthCollector.cs

@@ -15,6 +15,8 @@ public class SiteHealthCollector : ISiteHealthCollector
     private int _deadLetterCount;
     private readonly ConcurrentDictionary<string, ConnectionHealth> _connectionStatuses = new();
     private readonly ConcurrentDictionary<string, TagResolutionStatus> _tagResolutionCounts = new();
+    private IReadOnlyDictionary<string, int> _sfBufferDepths = new Dictionary<string, int>();
+    private int _deployedInstanceCount, _enabledInstanceCount, _disabledInstanceCount;
 
     /// <summary>
     /// Increment the script error counter. Covers unhandled exceptions,
@@ -68,6 +70,26 @@ public class SiteHealthCollector : ISiteHealthCollector
         _tagResolutionCounts[connectionName] = new TagResolutionStatus(totalSubscribed, successfullyResolved);
     }
 
+    /// <summary>
+    /// Set the current store-and-forward buffer depths snapshot.
+    /// Called before report collection with data from the S&amp;F service.
+    /// </summary>
+    public void SetStoreAndForwardDepths(IReadOnlyDictionary<string, int> depths)
+    {
+        _sfBufferDepths = depths;
+    }
+
+    /// <summary>
+    /// Set the current instance counts.
+    /// Called by the Deployment Manager after instance state changes.
+    /// </summary>
+    public void SetInstanceCounts(int deployed, int enabled, int disabled)
+    {
+        Interlocked.Exchange(ref _deployedInstanceCount, deployed);
+        Interlocked.Exchange(ref _enabledInstanceCount, enabled);
+        Interlocked.Exchange(ref _disabledInstanceCount, disabled);
+    }
+
     /// <summary>
     /// Collect the current health report for the site and reset interval counters.
     /// Connection statuses and tag resolution counts are NOT reset (they reflect current state).
@@ -84,8 +106,8 @@ public class SiteHealthCollector : ISiteHealthCollector
         var connectionStatuses = new Dictionary<string, ConnectionHealth>(_connectionStatuses);
         var tagResolution = new Dictionary<string, TagResolutionStatus>(_tagResolutionCounts);
 
-        // S&F buffer depth: placeholder (Phase 3C)
+        // Snapshot current S&F buffer depths
-        var sfBufferDepths = new Dictionary<string, int>();
+        var sfBufferDepths = new Dictionary<string, int>(_sfBufferDepths);
 
         return new SiteHealthReport(
             SiteId: siteId,
@@ -96,6 +118,9 @@ public class SiteHealthCollector : ISiteHealthCollector
             ScriptErrorCount: scriptErrors,
             AlarmEvaluationErrorCount: alarmErrors,
             StoreAndForwardBufferDepths: sfBufferDepths,
-            DeadLetterCount: deadLetters);
+            DeadLetterCount: deadLetters,
+            DeployedInstanceCount: _deployedInstanceCount,
+            EnabledInstanceCount: _enabledInstanceCount,
+            DisabledInstanceCount: _disabledInstanceCount);
     }
 }

src/ScadaLink.Host/Actors/AkkaHostedService.cs

@@ -118,8 +118,9 @@ akka {{
         // Register the dead letter monitor actor
         var loggerFactory = _serviceProvider.GetRequiredService<ILoggerFactory>();
         var dlmLogger = loggerFactory.CreateLogger<DeadLetterMonitorActor>();
+        var dlmHealthCollector = _serviceProvider.GetService<ScadaLink.HealthMonitoring.ISiteHealthCollector>();
         _actorSystem.ActorOf(
-            Props.Create(() => new DeadLetterMonitorActor(dlmLogger)),
+            Props.Create(() => new DeadLetterMonitorActor(dlmLogger, dlmHealthCollector)),
             "dead-letter-monitor");
 
         // Register role-specific actors
@@ -227,6 +228,9 @@ akka {{
             _logger.LogInformation("Data Connection Layer manager actor created");
         }
 
+        // Resolve the health collector for the Deployment Manager
+        var siteHealthCollector = _serviceProvider.GetService<ScadaLink.HealthMonitoring.ISiteHealthCollector>();
+
         // Create the Deployment Manager as a cluster singleton
         var singletonProps = ClusterSingletonManager.Props(
             singletonProps: Props.Create(() => new DeploymentManagerActor(
@@ -236,7 +240,8 @@ akka {{
                 streamManager,
                 siteRuntimeOptionsValue,
                 dmLogger,
-                dclManager)),
+                dclManager,
+                siteHealthCollector)),
             terminationMessage: PoisonPill.Instance,
             settings: ClusterSingletonManagerSettings.Create(_actorSystem!)
                 .WithRole(siteRole)

src/ScadaLink.Host/Actors/DeadLetterMonitorActor.cs

@@ -1,6 +1,7 @@
 using Akka.Actor;
 using Akka.Event;
 using Microsoft.Extensions.Logging;
+using ScadaLink.HealthMonitoring;
 
 namespace ScadaLink.Host.Actors;
 
@@ -11,12 +12,16 @@ namespace ScadaLink.Host.Actors;
 public class DeadLetterMonitorActor : ReceiveActor
 {
     private long _deadLetterCount;
+    private readonly ISiteHealthCollector? _healthCollector;
 
-    public DeadLetterMonitorActor(ILogger<DeadLetterMonitorActor> logger)
+    public DeadLetterMonitorActor(ILogger<DeadLetterMonitorActor> logger, ISiteHealthCollector? healthCollector = null)
     {
+        _healthCollector = healthCollector;
+
         Receive<DeadLetter>(dl =>
         {
             _deadLetterCount++;
+            _healthCollector?.IncrementDeadLetter();
             logger.LogWarning(
                 "Dead letter: {MessageType} from {Sender} to {Recipient}",
                 dl.Message.GetType().Name,

src/ScadaLink.SiteRuntime/Actors/AlarmActor.cs

@@ -4,6 +4,7 @@ using Microsoft.Extensions.Logging;
 using ScadaLink.Commons.Messages.Streaming;
 using ScadaLink.Commons.Types.Enums;
 using ScadaLink.Commons.Types.Flattening;
+using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Scripts;
 using System.Text.Json;
 
@@ -34,6 +35,7 @@ public class AlarmActor : ReceiveActor
     private readonly SharedScriptLibrary _sharedScriptLibrary;
     private readonly SiteRuntimeOptions _options;
     private readonly ILogger _logger;
+    private readonly ISiteHealthCollector? _healthCollector;
 
     private AlarmState _currentState = AlarmState.Normal;
     private readonly AlarmTriggerType _triggerType;
@@ -56,7 +58,8 @@ public class AlarmActor : ReceiveActor
         Script<object?>? onTriggerCompiledScript,
         SharedScriptLibrary sharedScriptLibrary,
         SiteRuntimeOptions options,
-        ILogger logger)
+        ILogger logger,
+        ISiteHealthCollector? healthCollector = null)
     {
         _alarmName = alarmName;
         _instanceName = instanceName;
@@ -64,6 +67,7 @@ public class AlarmActor : ReceiveActor
         _sharedScriptLibrary = sharedScriptLibrary;
         _options = options;
         _logger = logger;
+        _healthCollector = healthCollector;
         _priority = alarmConfig.PriorityLevel;
         _onTriggerScriptName = alarmConfig.OnTriggerScriptCanonicalName;
         _onTriggerCompiledScript = onTriggerCompiledScript;
@@ -164,6 +168,7 @@ public class AlarmActor : ReceiveActor
         }
         catch (Exception ex)
         {
+            _healthCollector?.IncrementAlarmError();
             // Alarm evaluation errors logged, actor continues
             _logger.LogError(ex,
                 "Alarm {Alarm} evaluation error on {Instance}",

src/ScadaLink.SiteRuntime/Actors/DeploymentManagerActor.cs

@@ -5,6 +5,7 @@ using ScadaLink.Commons.Messages.DebugView;
 using ScadaLink.Commons.Messages.Deployment;
 using ScadaLink.Commons.Messages.Lifecycle;
 using ScadaLink.Commons.Types.Enums;
+using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Persistence;
 using ScadaLink.SiteRuntime.Scripts;
 using ScadaLink.SiteRuntime.Streaming;
@@ -30,7 +31,9 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
     private readonly SiteRuntimeOptions _options;
     private readonly ILogger<DeploymentManagerActor> _logger;
     private readonly IActorRef? _dclManager;
+    private readonly ISiteHealthCollector? _healthCollector;
     private readonly Dictionary<string, IActorRef> _instanceActors = new();
+    private int _totalDeployedCount;
 
     public ITimerScheduler Timers { get; set; } = null!;
 
@@ -41,7 +44,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         SiteStreamManager? streamManager,
         SiteRuntimeOptions options,
         ILogger<DeploymentManagerActor> logger,
-        IActorRef? dclManager = null)
+        IActorRef? dclManager = null,
+        ISiteHealthCollector? healthCollector = null)
     {
         _storage = storage;
         _compilationService = compilationService;
@@ -49,6 +53,7 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         _streamManager = streamManager;
         _options = options;
         _dclManager = dclManager;
+        _healthCollector = healthCollector;
         _logger = logger;
 
         // Lifecycle commands
@@ -123,9 +128,11 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         }
 
         var enabledConfigs = msg.Configs.Where(c => c.IsEnabled).ToList();
+        _totalDeployedCount = msg.Configs.Count;
         _logger.LogInformation(
             "Loaded {Total} deployed configs ({Enabled} enabled) from SQLite",
             msg.Configs.Count, enabledConfigs.Count);
+        UpdateInstanceCounts();
 
         if (enabledConfigs.Count == 0)
             return;
@@ -200,6 +207,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
 
         // Create the Instance Actor immediately (no existing actor to replace)
         CreateInstanceActor(instanceName, command.FlattenedConfigurationJson);
+        _totalDeployedCount++;
+        UpdateInstanceCounts();
 
         // Persist to SQLite and clear static overrides asynchronously
         var sender = Sender;
@@ -257,6 +266,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
             _instanceActors.Remove(instanceName);
         }
 
+        UpdateInstanceCounts();
+
         var sender = Sender;
         _storage.SetInstanceEnabledAsync(instanceName, false).ContinueWith(t =>
         {
@@ -313,6 +324,7 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
         {
             CreateInstanceActor(instanceName, result.Config.ConfigJson);
         }
+        UpdateInstanceCounts();
 
         result.OriginalSender.Tell(new InstanceLifecycleResponse(
             result.Command.CommandId, instanceName, true, null, DateTimeOffset.UtcNow));
@@ -333,6 +345,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
             Context.Stop(actor);
             _instanceActors.Remove(instanceName);
         }
+        _totalDeployedCount = Math.Max(0, _totalDeployedCount - 1);
+        UpdateInstanceCounts();
 
         var sender = Sender;
         _storage.RemoveDeployedConfigAsync(instanceName).ContinueWith(t =>
@@ -536,7 +550,8 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
             _streamManager,
             _options,
             loggerFactory.CreateLogger<InstanceActor>(),
-            _dclManager));
+            _dclManager,
+            _healthCollector));
 
         var actorRef = Context.ActorOf(props, instanceName);
         _instanceActors[instanceName] = actorRef;
@@ -549,6 +564,18 @@ public class DeploymentManagerActor : ReceiveActor, IWithTimers
     /// </summary>
     internal int InstanceActorCount => _instanceActors.Count;
 
+    /// <summary>
+    /// Updates the health collector with current instance counts.
+    /// Total deployed = _totalDeployedCount, enabled = running actors, disabled = difference.
+    /// </summary>
+    private void UpdateInstanceCounts()
+    {
+        _healthCollector?.SetInstanceCounts(
+            deployed: _totalDeployedCount,
+            enabled: _instanceActors.Count,
+            disabled: _totalDeployedCount - _instanceActors.Count);
+    }
+
     // ── Internal messages ──
 
     internal record StartupConfigsLoaded(List<DeployedInstance> Configs, string? Error);

src/ScadaLink.SiteRuntime/Actors/InstanceActor.cs

@@ -8,6 +8,7 @@ using ScadaLink.Commons.Messages.ScriptExecution;
 using ScadaLink.Commons.Messages.Streaming;
 using ScadaLink.Commons.Types.Enums;
 using ScadaLink.Commons.Types.Flattening;
+using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Persistence;
 using ScadaLink.SiteRuntime.Scripts;
 using ScadaLink.SiteRuntime.Streaming;
@@ -37,6 +38,7 @@ public class InstanceActor : ReceiveActor
     private readonly SiteStreamManager? _streamManager;
     private readonly SiteRuntimeOptions _options;
     private readonly ILogger _logger;
+    private readonly ISiteHealthCollector? _healthCollector;
     private readonly Dictionary<string, object?> _attributes = new();
     private readonly Dictionary<string, string> _attributeQualities = new();
     private readonly Dictionary<string, AlarmState> _alarmStates = new();
@@ -61,7 +63,8 @@ public class InstanceActor : ReceiveActor
         SiteStreamManager? streamManager,
         SiteRuntimeOptions options,
         ILogger logger,
-        IActorRef? dclManager = null)
+        IActorRef? dclManager = null,
+        ISiteHealthCollector? healthCollector = null)
     {
         _instanceUniqueName = instanceUniqueName;
         _storage = storage;
@@ -71,6 +74,7 @@ public class InstanceActor : ReceiveActor
         _options = options;
         _logger = logger;
         _dclManager = dclManager;
+        _healthCollector = healthCollector;
 
         // Deserialize the flattened configuration
         _configuration = JsonSerializer.Deserialize<FlattenedConfiguration>(configJson);
@@ -474,7 +478,8 @@ public class InstanceActor : ReceiveActor
                 script,
                 _sharedScriptLibrary,
                 _options,
-                _logger));
+                _logger,
+                _healthCollector));
 
             var actorRef = Context.ActorOf(props, $"script-{script.CanonicalName}");
             _scriptActors[script.CanonicalName] = actorRef;
@@ -516,7 +521,8 @@ public class InstanceActor : ReceiveActor
                 onTriggerScript,
                 _sharedScriptLibrary,
                 _options,
-                _logger));
+                _logger,
+                _healthCollector));
 
             var actorRef = Context.ActorOf(props, $"alarm-{alarm.CanonicalName}");
             _alarmActors[alarm.CanonicalName] = actorRef;

src/ScadaLink.SiteRuntime/Actors/ScriptActor.cs

@@ -4,6 +4,7 @@ using Microsoft.Extensions.Logging;
 using ScadaLink.Commons.Messages.ScriptExecution;
 using ScadaLink.Commons.Messages.Streaming;
 using ScadaLink.Commons.Types.Flattening;
+using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Scripts;
 using System.Text.Json;
 
@@ -29,6 +30,7 @@ public class ScriptActor : ReceiveActor, IWithTimers
     private readonly SharedScriptLibrary _sharedScriptLibrary;
     private readonly SiteRuntimeOptions _options;
     private readonly ILogger _logger;
+    private readonly ISiteHealthCollector? _healthCollector;
 
     private Script<object?>? _compiledScript;
     private ScriptTriggerConfig? _triggerConfig;
@@ -46,7 +48,8 @@ public class ScriptActor : ReceiveActor, IWithTimers
         ResolvedScript scriptConfig,
         SharedScriptLibrary sharedScriptLibrary,
         SiteRuntimeOptions options,
-        ILogger logger)
+        ILogger logger,
+        ISiteHealthCollector? healthCollector = null)
     {
         _scriptName = scriptName;
         _instanceName = instanceName;
@@ -55,6 +58,7 @@ public class ScriptActor : ReceiveActor, IWithTimers
         _sharedScriptLibrary = sharedScriptLibrary;
         _options = options;
         _logger = logger;
+        _healthCollector = healthCollector;
         _minTimeBetweenRuns = scriptConfig.MinTimeBetweenRuns;
 
         // Parse trigger configuration
@@ -207,7 +211,8 @@ public class ScriptActor : ReceiveActor, IWithTimers
             _options,
             replyTo,
             correlationId,
-            _logger));
+            _logger,
+            _healthCollector));
 
         Context.ActorOf(props, executionId);
     }

src/ScadaLink.SiteRuntime/Actors/ScriptExecutionActor.cs

@@ -2,6 +2,7 @@ using Akka.Actor;
 using Microsoft.CodeAnalysis.Scripting;
 using Microsoft.Extensions.Logging;
 using ScadaLink.Commons.Messages.ScriptExecution;
+using ScadaLink.HealthMonitoring;
 using ScadaLink.SiteRuntime.Scripts;
 
 namespace ScadaLink.SiteRuntime.Actors;
@@ -28,7 +29,8 @@ public class ScriptExecutionActor : ReceiveActor
         SiteRuntimeOptions options,
         IActorRef replyTo,
         string correlationId,
-        ILogger logger)
+        ILogger logger,
+        ISiteHealthCollector? healthCollector = null)
     {
         // Immediately begin execution
         var self = Self;
@@ -37,7 +39,7 @@ public class ScriptExecutionActor : ReceiveActor
         ExecuteScript(
             scriptName, instanceName, compiledScript, parameters, callDepth,
             instanceActor, sharedScriptLibrary, options, replyTo, correlationId,
-            self, parent, logger);
+            self, parent, logger, healthCollector);
     }
 
     private static void ExecuteScript(
@@ -53,7 +55,8 @@ public class ScriptExecutionActor : ReceiveActor
         string correlationId,
         IActorRef self,
         IActorRef parent,
-        ILogger logger)
+        ILogger logger,
+        ISiteHealthCollector? healthCollector)
     {
         var timeout = TimeSpan.FromSeconds(options.ScriptExecutionTimeoutSeconds);
 
@@ -93,6 +96,7 @@ public class ScriptExecutionActor : ReceiveActor
             }
             catch (OperationCanceledException)
             {
+                healthCollector?.IncrementScriptError();
                 var errorMsg = $"Script '{scriptName}' on instance '{instanceName}' timed out after {timeout.TotalSeconds}s";
                 logger.LogWarning(errorMsg);
 
@@ -105,6 +109,7 @@ public class ScriptExecutionActor : ReceiveActor
             }
             catch (Exception ex)
             {
+                healthCollector?.IncrementScriptError();
                 // WP-32: Failures logged to site event log; script NOT disabled after failure
                 var errorMsg = $"Script '{scriptName}' on instance '{instanceName}' failed: {ex.Message}";
                 logger.LogError(ex, "Script execution failed: {Script} on {Instance}", scriptName, instanceName);

src/ScadaLink.SiteRuntime/ScadaLink.SiteRuntime.csproj

@@ -22,6 +22,7 @@
 
   <ItemGroup>
     <ProjectReference Include="../ScadaLink.Commons/ScadaLink.Commons.csproj" />
+    <ProjectReference Include="../ScadaLink.HealthMonitoring/ScadaLink.HealthMonitoring.csproj" />
   </ItemGroup>
 
 </Project>

tests/ScadaLink.Commons.Tests/Messages/MessageConventionTests.cs

@@ -98,7 +98,7 @@ public class MessageConventionTests
             },
             0, 0,
             new Dictionary<string, int> { ["queue1"] = 5 },
-            0);
+            0, 0, 0, 0);
 
         var json = JsonSerializer.Serialize(msg);
         var deserialized = JsonSerializer.Deserialize<ScadaLink.Commons.Messages.Health.SiteHealthReport>(json);

tests/ScadaLink.HealthMonitoring.Tests/CentralHealthAggregatorTests.cs

@@ -50,7 +50,10 @@ public class CentralHealthAggregatorTests
             ScriptErrorCount: 0,
             AlarmEvaluationErrorCount: 0,
             StoreAndForwardBufferDepths: new Dictionary<string, int>(),
-            DeadLetterCount: 0);
+            DeadLetterCount: 0,
+            DeployedInstanceCount: 0,
+            EnabledInstanceCount: 0,
+            DisabledInstanceCount: 0);
 
     [Fact]
     public void ProcessReport_StoresState_ForNewSite()

tests/ScadaLink.IntegrationTests/ObservabilityTests.cs

@@ -100,7 +100,10 @@ public class ObservabilityTests : IClassFixture<ScadaLinkWebApplicationFactory>
                 ["ext-system"] = 15,
                 ["notification"] = 2
             },
-            DeadLetterCount: 5);
+            DeadLetterCount: 5,
+            DeployedInstanceCount: 0,
+            EnabledInstanceCount: 0,
+            DisabledInstanceCount: 0);
 
         // Metric type 1: Data connection health
         Assert.Equal(2, report.DataConnectionStatuses.Count);
@@ -141,7 +144,7 @@ public class ObservabilityTests : IClassFixture<ScadaLinkWebApplicationFactory>
             "site-01", 1, DateTimeOffset.UtcNow,
             new Dictionary<string, ConnectionHealth>(),
             new Dictionary<string, TagResolutionStatus>(),
-            0, 0, new Dictionary<string, int>(), 0));
+            0, 0, new Dictionary<string, int>(), 0, 0, 0, 0));
 
         var state = aggregator.GetSiteState("site-01");
         Assert.NotNull(state);
@@ -152,7 +155,7 @@ public class ObservabilityTests : IClassFixture<ScadaLinkWebApplicationFactory>
             "site-01", 2, DateTimeOffset.UtcNow,
             new Dictionary<string, ConnectionHealth>(),
             new Dictionary<string, TagResolutionStatus>(),
-            3, 0, new Dictionary<string, int>(), 0));
+            3, 0, new Dictionary<string, int>(), 0, 0, 0, 0));
 
         state = aggregator.GetSiteState("site-01");
         Assert.Equal(2, state!.LastSequenceNumber);
@@ -174,7 +177,7 @@ public class ObservabilityTests : IClassFixture<ScadaLinkWebApplicationFactory>
                 "site-01", seq, DateTimeOffset.UtcNow,
                 new Dictionary<string, ConnectionHealth>(),
                 new Dictionary<string, TagResolutionStatus>(),
-                seq, 0, new Dictionary<string, int>(), 0));
+                seq, 0, new Dictionary<string, int>(), 0, 0, 0, 0));
         }
 
         var state = aggregator.GetSiteState("site-01");

tests/ScadaLink.PerformanceTests/HealthAggregationTests.cs

@@ -53,7 +53,10 @@ public class HealthAggregationTests
                 {
                     ["ext-system"] = i * 2
                 },
-                DeadLetterCount: 0);
+                DeadLetterCount: 0,
+                DeployedInstanceCount: 0,
+                EnabledInstanceCount: 0,
+                DisabledInstanceCount: 0);
 
             _aggregator.ProcessReport(report);
         }
@@ -83,7 +86,10 @@ public class HealthAggregationTests
                     ScriptErrorCount: seq % 5 == 0 ? 1 : 0,
                     AlarmEvaluationErrorCount: 0,
                     StoreAndForwardBufferDepths: new Dictionary<string, int>(),
-                    DeadLetterCount: 0);
+                    DeadLetterCount: 0,
+                DeployedInstanceCount: 0,
+                EnabledInstanceCount: 0,
+                DisabledInstanceCount: 0);
 
                 _aggregator.ProcessReport(report);
             }
@@ -111,14 +117,14 @@ public class HealthAggregationTests
             siteId, 10, DateTimeOffset.UtcNow,
             new Dictionary<string, ConnectionHealth>(),
             new Dictionary<string, TagResolutionStatus>(),
-            5, 0, new Dictionary<string, int>(), 0));
+            5, 0, new Dictionary<string, int>(), 0, 0, 0, 0));
 
         // Send stale report with seq 5 — should be rejected
         _aggregator.ProcessReport(new SiteHealthReport(
             siteId, 5, DateTimeOffset.UtcNow,
             new Dictionary<string, ConnectionHealth>(),
             new Dictionary<string, TagResolutionStatus>(),
-            99, 0, new Dictionary<string, int>(), 0));
+            99, 0, new Dictionary<string, int>(), 0, 0, 0, 0));
 
         var state = _aggregator.GetSiteState(siteId);
         Assert.NotNull(state);

tests/ScadaLink.SiteRuntime.Tests/ScadaLink.SiteRuntime.Tests.csproj

@@ -26,6 +26,7 @@
   <ItemGroup>
     <ProjectReference Include="../../src/ScadaLink.SiteRuntime/ScadaLink.SiteRuntime.csproj" />
     <ProjectReference Include="../../src/ScadaLink.Commons/ScadaLink.Commons.csproj" />
+    <ProjectReference Include="../../src/ScadaLink.HealthMonitoring/ScadaLink.HealthMonitoring.csproj" />
   </ItemGroup>
 
 </Project>