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Manually instrument .NET applications for Splunk Observability Cloud 🔗

The Splunk Distribution of OpenTelemetry .NET automatic instrumentation provides a base you can build on by adding your own manual instrumentation. By using both automatic and manual instrumentation, you can better instrument the logic and functionality of your applications, clients, and frameworks.

Create custom traces 🔗

To create custom spans and traces, follow these steps:

  1. Install the Splunk Distribution of OpenTelemetry .NET. See Instrument your .NET application.

  2. Add the System.Diagnostics.DiagnosticSource dependency to your project:

    <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="8.0.0" />

  3. Create an ActivitySource instance:

    private static readonly ActivitySource RegisteredActivity = new ActivitySource("Examples.ManualInstrumentations.Registered");

  4. Create an Activity. Optionally, set tags:

    using (var activity = RegisteredActivity.StartActivity("Main"))
{
   activity?.SetTag("foo", "bar1");
   // your logic for Main activity
}

  1. Register your ActivitySource by setting the OTEL_DOTNET_AUTO_TRACES_ADDITIONAL_SOURCES environmental variable. You can set the value to either Examples.ManualInstrumentations.Registered or to Examples.ManualInstrumentations.*, which registers the entire prefix.

See the OpenTelemetry official documentation for additional information and examples.

Create custom metrics 🔗

To create custom metrics, follow these steps:

  1. Add the System.Diagnostics.DiagnosticSource dependency to your project:

    <PackageReference Include="System.Diagnostics.DiagnosticSource" Version="8.0.0" />

  2. Create a Meter instance:

    using var meter = new Meter("My.Application", "1.0");

  3. Create an Instrument instance:

    var counter = meter.CreateCounter<long>("custom.counter", description: "Custom counter's description");

  4. Update the Instrument value:

    counter.Add(1);

  5. Register your Meter with OpenTelemetry.AutoInstrumentation by setting the OTEL_DOTNET_AUTO_METRICS_ADDITIONAL_SOURCES environment variable:

    OTEL_DOTNET_AUTO_METRICS_ADDITIONAL_SOURCES=My.Application

See the OpenTelemetry official documentation <https://opentelemetry.io/docs/languages/net/instrumentation/#metrics for additional information and examples.