Observability pipeline

Telemetry remains the small OTLP-only resource for routerd's own metrics, traces, and logs. LogSink describes log forwarding routes for operational events and observed network logs; an OTLP LogSink should reference a Telemetry resource rather than duplicating collector endpoints. Use ObservabilityPipeline when the router should also forward routerd event logs to pipeline-style remote sinks such as Loki.

ObservabilityPipeline is a built-in pipeline, not a bundled otelcol process. routerd still uses the normal OpenTelemetry SDK for OTLP logs, metrics, and traces, and it starts a lightweight event exporter for configured log sinks.

Supported log sinks today:

• stdout: JSON event lines, useful for supervised service logs.
• syslog: local or remote syslog using the existing LogSink syslog shape.
• loki: HTTP push to /loki/api/v1/push.

kafka is accepted as documented metadata only so configs can record the intended external pipeline, but routerd does not publish to Kafka directly yet.

Example:

apiVersion: system.routerd.net/v1alpha1
kind: ObservabilityPipeline
metadata:
  name: remote-observability
spec:
  otlp:
    endpoint: http://otel-collector.lan:4317
    insecure: true
    headers:
      authorization: Bearer example-token
  serviceNamespace: routerd
  attributes:
    site: edge
  signals: [logs, metrics, traces]
  sampling:
    rate: 1
  logs:
    sinks:
      - name: loki
        type: loki
        minLevel: info
        loki:
          url: http://loki.lan:3100/loki/api/v1/push
          tenant: routerd

The OTLP fields render to the standard OpenTelemetry environment variables for routerd-managed units. The log sink exporter subscribes to routerd.** events on the in-process bus, so it forwards controller status changes and daemon events without scraping journalctl.

Sampling is deterministic per pipeline and applies before sink fan-out. Keep it at 1 for operational event logs unless a high-volume source is intentionally being downsampled.

See examples/observability-loki.yaml for a complete config.