# OpcSubscriptionDiagnostics Class

> Reference: Provides diagnostic information about the operations performed and activities recognized on a OpcSubscription.

<dl class="api-definition">
<dt>Namespace</dt>
<dd><a href="../namespaces/opc.uafx.server">Opc.UaFx.Server</a></dd>
<dt>Assembly</dt>
<dd>Opc.UaFx.Advanced.dll</dd>
<dt>Package</dt>
<dd>Opc.UaFx.Advanced v2.59.0</dd>
<dt>Members</dt>
<dd><a href="./members">OpcSubscriptionDiagnostics Members</a></dd>
</dl>

Provides diagnostic information about the operations performed and activities recognized on a [OpcSubscription](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscription/).

## Syntax

<div class="api-signature" data-lang="csharp">

```csharp
public class OpcSubscriptionDiagnostics
```

</div>

<div class="api-signature" data-lang="vbnet">

```vbnet
Public Class OpcSubscriptionDiagnostics
```

</div>

## Inheritance

[Object](https://learn.microsoft.com/dotnet/api/system.object) → **OpcSubscriptionDiagnostics**

## Remarks

The properties provide the current values of the counters the server maintains for the subscription. A counter whose value is [MaxValue](https://learn.microsoft.com/dotnet/api/system.int32.maxvalue) or [MaxValue](https://learn.microsoft.com/dotnet/api/system.uint32.maxvalue) is provided as 0, and a counter above [MaxValue](https://learn.microsoft.com/dotnet/api/system.int32.maxvalue) is not provided correctly.

## Properties

| Name | Description |
|---|---|
| [CurrentKeepAliveCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#currentkeepalivecount) | Gets the current keep-alive counter of the subscription, i.e. the number of publishing intervals since the subscription has last sent a message. |
| [CurrentLifetimeCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#currentlifetimecount) | Gets the current lifetime counter of the subscription, i.e. the number of consecutive publishing intervals in which the subscription has waited for a publish request of the client. |
| [DataChangeNotificationsCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#datachangenotificationscount) | Gets the number of data change notifications the subscription has sent. |
| [DisableCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#disablecount) | Gets the number of times publishing has been disabled for the subscription. |
| [DisabledMonitoredItemCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#disabledmonitoreditemcount) | Gets the number of monitored items of the subscription whose monitoring mode is disabled. |
| [DiscardedMessageCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#discardedmessagecount) | Gets the number of messages of the subscription which the server has discarded. |
| [EnableCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#enablecount) | Gets the number of times publishing has been enabled for the subscription. |
| [EventNotificationsCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#eventnotificationscount) | Gets the number of event notifications the subscription has sent. |
| [EventQueueOverFlowCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#eventqueueoverflowcount) | Gets the number of times the event queue of a monitored item of the subscription has overflowed. |
| [LatePublishRequestCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#latepublishrequestcount) | Gets the number of publishing intervals which have elapsed while the subscription was waiting for a publish request of the client. |
| [MaxKeepAliveCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#maxkeepalivecount) | Gets the maximum keep-alive count of the subscription. |
| [MaxLifetimeCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#maxlifetimecount) | Gets the maximum lifetime count of the subscription. |
| [MaxNotificationsPerPublish](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#maxnotificationsperpublish) | Gets the maximum number of notifications the subscription sends in one message. |
| [ModifyCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#modifycount) | Gets the number of times the subscription has been modified. |
| [MonitoredItemCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#monitoreditemcount) | Gets the number of monitored items of the subscription. |
| [MonitoringQueueOverflowCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#monitoringqueueoverflowcount) | Gets the number of times the queue of a monitored item of the subscription has overflowed. |
| [NextSequenceNumber](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#nextsequencenumber) | Gets the sequence number of the next message of the subscription. |
| [NotificationsCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#notificationscount) | Gets the number of notifications the subscription has sent. |
| [PublishRequestCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#publishrequestcount) | Gets the number of publish requests the subscription has processed. |
| [RepublishMessageCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#republishmessagecount) | Gets the number of messages the subscription has sent again on a republish request. |
| [RepublishMessageRequestCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#republishmessagerequestcount) |  |
| [RepublishRequestCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#republishrequestcount) | Gets the number of republish requests the subscription has received. |
| [TransferredToAlternativeClientsCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#transferredtoalternativeclientscount) | Gets the number of times the subscription has been transferred to a session of another client. |
| [TransferredToSameClientCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#transferredtosameclientcount) | Gets the number of times the subscription has been transferred to another session of the same client. |
| [TransferRequestCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#transferrequestcount) | Gets the number of requests to transfer the subscription to another session. |
| [UnacknowledgedMessageCount](https://www.traeger.de/en/docs/development/opcua/api/v2.59/opc.uafx.server.opcsubscriptiondiagnostics/members#unacknowledgedmessagecount) | Gets the number of messages of the subscription which the client has not yet acknowledged. |

## Applies to

| Package | Versions |
|---|---|
| Opc.UaFx.Advanced | v2.5–v2.59 |