Configure the EDOT .NET SDK

Elastic Stack Serverless Observability

Configure the Elastic Distribution of OpenTelemetry .NET (EDOT .NET) to send data to Elastic.

Configure the OpenTelemetry SDK using the mechanisms listed in the OpenTelemetry documentation, including:

• Setting environment variables.
• Using the IConfiguration integration.
• Manually configuring EDOT .NET.

Configuration options set manually in code take precedence over environment variables, and environment variables take precedence over configuration options set using the IConfiguration system.

You can configure EDOT .NET using environment variables. This is a cross-platform way to configure EDOT .NET and is especially useful in containerized environments.

Environment variables are read at startup and can be used to configure EDOT .NET. For details of the various EDOT-specific options available and their corresponding environment variable names, see Configuration options.

All OpenTelemetry environment variables from the upstream SDK may also be used to configure the SDK behavior for features such as resources, samples and exporters.

In applications that use the ".NET generic host", such as ASP.NET Core and worker services, EDOT .NET can be configured using the IConfiguration integration.

When using an IHostApplicationBuilder in modern ASP.NET Core applications, the AddElasticOpenTelemetry extension method turns on EDOT .NET and configuration from IHostApplicationBuilder.Configuration is passed in automatically. For example:

var builder = WebApplication.CreateBuilder(args);
// Configuration is automatically bound and can be provided
// via the `appsettings.json` file.
builder.AddElasticOpenTelemetry();

By default, at this stage the configuration is populated from the default configuration sources, including the appsettings.json file(s) and command-line arguments. You can use these sources to define the configuration for the Elastic Distribution of OpenTelemetry .NET.

For example, you can define the configuration for the Elastic Distribution of OpenTelemetry .NET in the appsettings.json file:

{
  "Elastic": {
    "OpenTelemetry": {
      "LogDirectory": "C:\\Logs"
    }
  }
}

Configuration parsed from the Elastic:OpenTelemetry section of the IConfiguration instance is bound to the ElasticOpenTelemetryOptions instance used to configure EDOT .NET.

In situations where the application might not depend on the hosting APIs, but uses the dependency injection APIs instead, an IConfiguration instance can be passed in manually. This is usually the case with console applications. For example:

var configuration = new ConfigurationBuilder()
    .AddInMemoryCollection(new Dictionary<string, string?>()
    {
        ["Elastic:OpenTelemetry:LogDirectory"] = "C:\\Logs"
    })
    .Build();

var services = new ServiceCollection();
services.AddElasticOpenTelemetry(configuration);

To learn more about the Microsoft configuration system, see Configuration in ASP.NET Core.

In all other scenarios, you can configure EDOT .NET manually in code.

Create an instance of ElasticOpenTelemetryOptions and pass it to an overload of the WithElasticDefaults extension methods available on the IHostApplicationBuilder, the IServiceCollection and the specific signal providers such as TracerProviderBuilder.

For example, in traditional console applications, you can configure the Elastic Distribution of OpenTelemetry .NET like this:

using OpenTelemetry;
using Elastic.OpenTelemetry;

// Create an instance of `ElasticOpenTelemetryOptions`.
var options = new ElasticOpenTelemetryOptions
{
  // This example sets the file log directory to `C:\Logs`
  // which enables diagnostic file logging.
  FileLogDirectory = "C:\\Logs"
};

// Pass the `ElasticOpenTelemetryOptions` instance to the
// `WithElasticDefaults` extension method for the `IOpenTelemetryBuilder`
//  to configure EDOT .NET.
using var sdk = OpenTelemetrySdk.Create(builder => builder
  .WithElasticDefaults(options));

Because the Elastic Distribution of OpenTelemetry .NET (EDOT .NET) is an extension of the OpenTelemetry .NET SDK, it supports both:

• General OpenTelemetry SDK configuration options
• Elastic-specific configuration options that are only available when using EDOT .NET

EDOT .NET supports all configuration options listed in the OpenTelemetry General SDK Configuration documentation.

EDOT .NET supports the following Elastic-specific options.

• Type: String
• Default: string.Empty

A string specifying the output directory where the Elastic Distribution of OpenTelemetry .NET writes diagnostic log files. When not provided, no file logging occurs. Each new .NET process creates a new log file in the specified directory.

• Type: String
• Default: Information

Sets the logging level for EDOT .NET. Valid options are Critical, Error, Warning, Information, Debug, Trace, and None. None disables the logging.

• Type: String
• Default: Information

A comma-separated list of targets for log output. When global logging is not configured (a log directory or target is not specified) this defaults to none. When the instrumented application is running within a container, this defaults to direct logs to stdout. Otherwise defaults to file.

Valid options are file, stdout and none. None disables the logging.

• Type: Bool
• Default: false

Allows EDOT .NET to be used with its defaults, but without enabling the export of telemetry data to an OTLP endpoint. This can be useful when you want to test applications without sending telemetry data.

• Type: Bool
• Default: false

Allows EDOT .NET to be used without the instrumentation assembly scanning feature turned on. This prevents the automatic registration of instrumentation from referenced OpenTelemetry contrib instrumentation packages.