.NET

This guide shows how to send .NET application logs to Coralogix using the OpenTelemetry .NET SDK with Microsoft.Extensions.Logging, the OTLP log exporter, and a Resource that sets service.name, cx.application.name, and cx.subsystem.name. This replaces shipping logs through the legacy Coralogix .NET SDK.

Use a supported .NET version (8.0 or later is recommended) with current OpenTelemetry.* packages.

Package dependencies setup

Create a console application and add the OpenTelemetry SDK, OTLP exporter, and logging packages (versions are examples; use the latest compatible releases from NuGet):

dotnet new console -n DotnetOtelLogsSample -o DotnetOtelLogsSample
cd DotnetOtelLogsSample
dotnet add package OpenTelemetry --version 1.15.3
dotnet add package OpenTelemetry.Exporter.OpenTelemetryProtocol --version 1.15.3
dotnet add package Microsoft.Extensions.Logging --version 8.0.0

Select the https://ingress. endpoint that corresponds to your Coralogix domain using the domain selector at the top of the page.

Application implementation

1. Build a ResourceBuilder with AddService for service.name (and version), then add cx.application.name and cx.subsystem.name as resource attributes.
2. Call LoggerFactory.Create with AddOpenTelemetry and AddOtlpExporter, pointing at your OTLP/gRPC endpoint (the sample defaults to http://localhost:4317 for a local collector).
3. Create an ILogger with a category name (for example the class name). Emit logs at the level you need; the sample uses LogError to match a simple smoke test.

Replace Program.cs with the following:

using System;
using System.Collections.Generic;
using System.Threading;
using Microsoft.Extensions.Logging;
using OpenTelemetry.Logs;
using OpenTelemetry.Resources;

namespace DotnetOtelLogsSample;

internal static class Program
{
    private static void Main()
    {
        var endpoint = Environment.GetEnvironmentVariable("OTEL_EXPORTER_OTLP_ENDPOINT")
            ?? "http://localhost:4317";
        var serviceName = Environment.GetEnvironmentVariable("OTEL_SERVICE_NAME")
            ?? "dotnet-otel-logs-sample";
        var applicationName = Environment.GetEnvironmentVariable("CORALOGIX_APPLICATION")
            ?? "dotnet-otel-app";
        var subsystemName = Environment.GetEnvironmentVariable("CORALOGIX_SUBSYSTEM")
            ?? "worker";

        var resourceBuilder = ResourceBuilder.CreateDefault()
            .AddService(serviceName: serviceName, serviceVersion: "1.0.0")
            .AddAttributes(new Dictionary<string, object>
            {
                ["cx.application.name"] = applicationName,
                ["cx.subsystem.name"] = subsystemName,
            });

        using var loggerFactory = LoggerFactory.Create(builder =>
        {
            builder.AddOpenTelemetry(logging =>
            {
                logging.SetResourceBuilder(resourceBuilder);
                logging.AddOtlpExporter(options =>
                {
                    options.Endpoint = new Uri(endpoint);
                });
            });
        });

        var logger = loggerFactory.CreateLogger("My class");

        var i = 0;
        do
        {
            logger.LogError("Hello World Coralogix");
            i++;
            Thread.Sleep(1000);
        } while (i < 5);

        Thread.Sleep(1500);
        Console.WriteLine("Done: flush window completed");
    }
}

Run the sample:

dotnet run

Notes

• The OTLP exporter batches records. Keep the process alive briefly after your last log (as in the sample) so batches can export before exit.
• If you upgrade packages, follow the OpenTelemetry .NET logs documentation for any API or package layout changes.
• For a broader walkthrough (shared resource builders, traces, and metrics), see .NET OpenTelemetry instrumentation.

Logging output

With the OpenTelemetry SDK, you can send logs either to a local OpenTelemetry Collector or directly to Coralogix using an OTLP endpoint.

OpenTelemetry Collector

Set OTEL_EXPORTER_OTLP_ENDPOINT to your collector’s OTLP/gRPC address (often http://localhost:4317 or http://collector:4317). With a debug exporter on the collector, log records show resource attributes such as cx.application.name, cx.subsystem.name, and service.name, plus the log body and severity.

Coralogix OpenTelemetry endpoint

Authenticate with your Send-Your-Data API key and point the OTLP exporter at your Coralogix endpoint. The sample reads CORALOGIX_APPLICATION and CORALOGIX_SUBSYSTEM for cx.application.name and cx.subsystem.name (defaults match a local collector; override them when sending to Coralogix).

OTEL_EXPORTER_OTLP_ENDPOINT=https://ingress.:443
OTEL_EXPORTER_OTLP_HEADERS="Authorization=Bearer send_your_data_key"
OTEL_SERVICE_NAME=dotnet-otel-logs-sample
CORALOGIX_APPLICATION=hello
CORALOGIX_SUBSYSTEM=world

In Explore logs, application and subsystem filters reflect those resource attributes; expanded rows show logRecord.body, severity, and resource.attributes.service.name.

Additional resources

Support

For help, use in-app chat or email [email protected].