ASP.NET health monitoring allows production and operations staff to manage deployed Web applications. The System.Web.Management namespace contains the health-event types responsible for packaging application health-status data and the provider types responsible for processing this data. It also contains supporting types that help during the management of health events.

The System.Web.Management.WebEventCodes class contains codes that identify types of health-monitoring events. Two types of codes are defined within the class: major codes, which identify the ASP.NET health-monitoring events; and detail codes, which provide more information about a related major code. These codes are implemented as integers, rather than as an enumeration, to allow for extensibility.

When a health-monitoring event is raised, it is associated with a major event code. The following list identifies the categories of major event codes that are defined within the System.Web.Management.WebEventCodes class:

• Application codes. Application codes identify events in the lifetime of an application, such as startup and shutdown events. Their values are greater than the WebEventCodes.ApplicationCodeBase field constant. They are associated with the System.Web.Management.WebApplicationLifetimeEvent event type. The heartbeat event is a special kind of application event. It identifies events raised at periodic intervals to provide information relative to the state of the running process. It is associated with the System.Web.Management.WebHeartbeatEvent event type.

• Request codes. Request codes identify non-error events that provide per-request information. Their values are greater than the WebEventCodes.RequestCodeBase field constant. They are associated with the System.Web.Management.WebRequestEvent event type.

• Error codes. Error codes identify events that contain information about two kinds of errors: errors specifically related to a Web request and systemic errors. The errors related to Web requests include unhandled exceptions, view-state errors, and input-validation errors. They are associated with the System.Web.Management.WebRequestErrorEvent event type. The systemic errors relate to configuration or application code, including parser errors and compilation errors. They are associated with the System.Web.Management.WebErrorEvent event type. Both kinds of errors have values greater than the WebEventCodes.ErrorCodeBase field constant.

• Audit codes. Audit codes identify events that contain auditable information such as login attempts, access security violations, and authorization violations. Their values are greater than WebEventCodes.AuditCodeBase. They are associated with System.Web.Management.WebAuditEvent and its derived event types.

• Miscellaneous codes. Miscellaneous codes do not identify events but are used to flag nonstandard event information. Their values are greater than WebEventCodes.MiscCodeBase. Refer also to WebEventCodes.WebEventProviderInformation for more information.

You can create your own custom event code by choosing code values above WebEventCodes.WebExtendedBase.

In the eventMappings health-monitoring configuration element, you can optionally specify an event-code range. If the event code range is specified, the mapping only applies to the events that have an event code within that range; otherwise, it applies to all the event codes. The following configuration file excerpt shows the System.Web.Management.EventLogWebEventProvider configured to handle System.Web.Management.WebFailureAuditEvent events whose event codes belong to the audit category.

<healthMonitoring>
  <eventMappings> 
    <add name="Failure Audits" type=
      "System.Web.Management.WebFailureAuditEvent,System.Web, Version=2.0.3600.0,Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
  </eventMappings>

  <rules>
    <add name="Failure Audits Default"
      eventName="Failure Audits"
      provider="EventLogProvider"
      profile="Default"
      minInterval="00:01:00" />
  </rules>
</healthMonitoring>

You can create your own custom event code by choosing code values above WebEventCodes.WebExtendedBase.