WN: v10 RC1: Identity metrics (#36076)

* WN: v10 RC1: Identity metrics

* lowercase include filename

* Fixed link

* Minor edits

Author: wadepickett

aspnetcore/release-notes/aspnetcore-10.0.md

@@ -90,6 +90,8 @@ The following image shows an example of the Authenticated request duration metri
 
 For more information, see <xref:log-mon/metrics/built-in#microsoftaspnetcoreauthorization>.
 
+[!INCLUDE[](~/release-notes/aspnetcore-10/includes/identity-metrics.md)]
+
 [!INCLUDE[](~/release-notes/aspnetcore-10/includes/avoid-cookie-login-redirects.md)]
 
 ## Miscellaneous

aspnetcore/release-notes/aspnetcore-10/includes/identity-metrics.md

@@ -0,0 +1,25 @@
+### ASP.NET Core Identity metrics
+
+[ASP.NET Core Identity](xref:security/authentication/identity) observability has been improved in .NET 10 with metrics. Metrics are counters, histograms, and gauges that provide time-series measurements of system or application behavior.
+
+For example, use the new ASP.NET Core Identity metrics to observe:
+
+* **User management**: New user creations, password changes, and role assignments.
+* **Login/session handling**: Login attempts, sign ins, sign outs, and users using two factor authentication.
+
+The new metrics are in the `Microsoft.AspNetCore.Identity` meter:
+
+* `aspnetcore.identity.user.create.duration`
+* `aspnetcore.identity.user.update.duration`
+* `aspnetcore.identity.user.delete.duration`
+* `aspnetcore.identity.user.check_password_attempts`
+* `aspnetcore.identity.user.generated_tokens`
+* `aspnetcore.identity.user.verify_token_attempts`
+* `aspnetcore.identity.sign_in.authenticate.duration`
+* `aspnetcore.identity.sign_in.check_password_attempts`
+* `aspnetcore.identity.sign_in.sign_ins`
+* `aspnetcore.identity.sign_in.sign_outs`
+* `aspnetcore.identity.sign_in.two_factor_clients_remembered`
+* `aspnetcore.identity.sign_in.two_factor_clients_forgotten`
+
+For more information about using metrics in ASP.NET Core, see <xref:log-mon/metrics/metrics>.