Blackbox Exporter Synthetic Monitoring Guide
This page explains how Blackbox Exporter is used in the monitoring repository for endpoint probing.
Key File
blackbox/blackbox.yml
What Blackbox Exporter Does
Unlike Node Exporter or cAdvisor, Blackbox Exporter does not collect host or container resource metrics directly.
Instead, it performs probe-style checks such as:
- HTTP reachability
- Response success or failure
- Basic latency visibility
How It Is Used in This Stack
The repository uses Blackbox Exporter to probe internal HTTP targets such as:
- Grafana
- Prometheus
- cAdvisor
- Alertmanager
- Loki
This complements normal metrics scraping because a service can look healthy internally while still being unreachable to a client or probe.
Why Synthetic Checks Matter
Synthetic monitoring answers a different question:
- Exporter metrics answer: "Is the service reporting metrics?"
- Blackbox answers: "Can something actually reach and use the endpoint?"
Both are valuable.
Good Metrics to Watch
- Probe success
- Probe duration
- HTTP status result
- Failure frequency over time
Good Follow-Up Improvements
- Add external URL checks
- Add HTTPS validation
- Add DNS and TCP probe modules
- Label probe targets by service and environment
Verification
docker compose logs -f blackbox
curl http://localhost:9115