Unable to capture logs using OpenTelemetry collector in Grafana Agent

Question

I'm trying to setup logs with .NET and OpenTelemetry.

My goal is to send the logs to the Grafana Agent and then forward them to the collector

//Program.cs
var builder = WebApplication.CreateBuilder(args);

builder.Logging.ClearProviders();
builder.Logging.AddConsole();

var otel = builder.Services.AddOpenTelemetry();
otel.ConfigureResource(resource => resource
                          .AddService(builder.Environment.ApplicationName));

builder.Logging.AddOpenTelemetry(options =>
   {
      options.IncludeScopes = true;
      options.IncludeFormattedMessage = true;
      options.ParseStateValues = true;
      options.AddOtlpExporter(otlpOptions =>
         {
            otlpOptions.Endpoint = new Uri("http://localhost:4318");
         });
   });

var app = builder.Build();
app.MapGet("/", SendGreeting);
app.Run();

async Task<String> SendGreeting(ILogger<Program> logger)
   {
      logger.LogInformation("Test Log");
      return "Hello World!";
   }

Docker-compose.yml

services:
  grafana:
    image: grafana/grafana-oss:latest
    ports:
      - '3000:3000'
    networks:
      - monitoring
    volumes:
      - grafana-storage:/var/lib/grafana
    environment:
      - GF_SECURITY_ADMIN_USER=admin
      - GF_SECURITY_ADMIN_PASSWORD=admin

  grafana-agent:
    image: grafana/agent:latest
    ports:
      - "12345:12345"
    volumes:
      - ./grafana-agent.yaml:/etc/agent.yaml
    command:
      - "--config.file=/etc/agent.yaml"
    networks:
      - monitoring  

  otel-collector:
    image: otel/opentelemetry-collector-contrib
    volumes:
      - ./otel-collector-config.yaml:/etc/otel-collector-config.yaml
    ports:
      - 1888:1888 # pprof extension
      - 8888:8888 # Prometheus metrics exposed by the Collector
      - 8889:8889 # Prometheus exporter metrics
      - 13133:13133 # health_check extension
      - 4317:4317 # OTLP gRPC receiver
      - 4318:4318 # OTLP http receiver
      - 55679:55679 # zpages extension
    command: ["--config=/etc/otel-collector-config.yaml"]
    networks:
      - monitoring
volumes:
  grafana-storage:

networks:
  monitoring:

grafana-agent.yml

server:
  log_level: info

logs:
  configs:
    - name: otel-logs
      positions:
        filename: /tmp/positions.yaml
      scrape_configs:
        - job_name: otel-logs
          static_configs:
            - targets: ['localhost']
              labels:
                job: otel-logs
                __path__: /var/log/*.log
      clients:
        - url: http://otel-collector:4318

otel-collector-config.yaml

receivers:
  otlp:
    protocols:
      http:
exporters:
  logging:
    loglevel: info
service:
  telemetry:
    logs:
      level: info
  pipelines:
    logs:
      receivers: [otlp]
      exporters: [logging]

The logs reach the console (ConsoleExporter), but I don’t see them in the collector’s stdout logs

What am I doing wrong?

Answer 1

turns out the problem was in the config for collector

proper configuration:

receivers:
  otlp:
    protocols:
      grpc:
        endpoint: 0.0.0.0:4317
processors:
  batch:

exporters:
  debug:
    verbosity: detailed

service:
  pipelines:
    logs:
      receivers: [otlp]
      processors: [batch]
      exporters: [debug]