.NET distributed tracing

Distributed tracing is a diagnostic technique that helps engineers localize failures and performance issues within applications, especially those that may be distributed across multiple machines or processes. This technique tracks requests through an application correlating together work done by different application components and separating it from other work the application may be doing for concurrent requests. For example, a request to a typical web service might be first received by a load balancer, then forwarded to a web server process, which then makes several queries to a database. Using distributed tracing allows engineers to distinguish if any of those steps failed, how long each step took, and potentially logging messages produced by each step as it ran.

Getting started for .NET app developers

Key .NET libraries are instrumented to produce distributed tracing information automatically. However, this information needs to be collected and stored so that it will be available for review later. Typically, app developers select a telemetry service that stores this trace information for them and then use a corresponding library to transmit the distributed tracing telemetry to their chosen service:

• OpenTelemetry is a vendor-neutral library that supports several services. For more information, see Collect distributed traces with OpenTelemetry.
• Application Insights is a full-featured service provided by Microsoft. For more information, see Collect distributed traces with Application Insights.
• There are many high-quality third-party application performance monitoring (APM) vendors that offer integrated .NET solutions.

For more information, see Understand distributed tracing concepts and the following guides:

• Collect distributed traces with custom logic
• Adding custom distributed trace instrumentation

For third-party telemetry collection services, follow the setup instructions provided by the vendor.

Getting started for .NET library developers

.NET libraries don't need to be concerned with how telemetry is ultimately collected, only with how it is produced. If you want consumers of your library to be able to see the work that it does detailed in a distributed trace, add distributed tracing instrumentation to support it.

For more information, see Understand distributed tracing concepts and the Adding custom distributed trace instrumentation guide.