Docs » Supported integrations in Splunk Observability Cloud » Instrument back-end applications to send spans to Splunk APM » Instrument .NET applications for Splunk Observability Cloud (OpenTelemetry) » SignalFx Instrumentation for .NET (Deprecated) » Manually instrument .NET applications for Splunk Observability Cloud


The SignalFx Instrumentation for .NET is deprecated as of February 21, 2024 and will reach End of Support on February 21 2025. Until then, only critical security fixes and bug fixes will be provided. After the date, the library will be archived and no longer maintained.

New customers instrumenting the .NET ecosystem should use the Splunk Distribution of OpenTelemetry .NET. Existing customers should consider migrating to Splunk Distribution of OpenTelemetry .NET which offers similar capabilities. To learn how to migrate, see Migrate from the SignalFx .NET Instrumentation.

Manually instrument .NET applications for Splunk Observability Cloud 🔗

The SignalFx Instrumentation for .NET provides and registers an OpenTracing-compatible global tracer that you can use to instrument your applications manually for Splunk Observability Cloud. Custom or manual instrumentation can be helpful when you need to add custom attributes to spans, or need to generate spans manually.


The SignalFx Instrumentation for .NET supports OpenTracing version 0.12.1 and higher.

To instrument your .NET application manually, follow these steps:

  1. Add the OpenTracing dependency to your project:

    <PackageReference Include="OpenTracing" Version="0.12.1" />
  2. Obtain the OpenTracing.Util.GlobalTracer instance and create spans:

    using OpenTracing;
    using OpenTracing.Util;
    namespace MyProject
       public class MyClass
          public static async void MyMethod()
             // Obtain the automatically registered OpenTracing.Util.GlobalTracer instance
             var tracer = GlobalTracer.Instance;
             // Create an active span that automatically becomes a child span of any existing span in this context
             using (IScope scope = tracer.BuildSpan("MyTracedFunctionality").StartActive(finishSpanOnDispose: true))
                var span = scope.Span;
                span.SetTag("MyTag", "MyValue");
                span.Log("My Log Statement");
                var ret = await MyAppFunctionality();
                span.SetTag("FunctionalityReturned", ret.ToString());