OpenTelemetry Collector

The OpenTelemetry Collector is the vendor-neutral middleman that collects logs, metrics, and traces from your applications and routes them wherever you want. Instead of installing five different agents for five different observability tools, you install one Collector and configure where data goes. Switch backends without changing your app code. Apache 2.0. CNCF project backed by every major observability vendor. The Collector receives telemetry data, processes it (filter, transform, sample, batch), and exports it to one or more backends simultaneously.

Fully free. No paid tier. The Collector itself is just the pipeline. You still need somewhere to send data (Grafana stack is free self-hosted, or pay for Datadog/New Relic/etc.).

The Collector runs as a sidecar, DaemonSet, or standalone deployment. The contrib distribution includes 200+ receivers, processors, and exporters for every major backend.

The catch: configuration is YAML-based and gets complex fast. Debugging pipeline issues (why aren't my traces showing up?) requires understanding the receiver-processor-exporter chain. And the Collector is infrastructure you need to monitor. Yes, you need observability for your observability pipeline.