Blackbox exporter is a Prometheus exporter that probes endpoints over HTTP, HTTPS, DNS, TCP, ICMP, and gRPC to generate metrics about their availability and performance.
The tool solves the problem of monitoring external services and endpoints that cannot be directly instrumented. Rather than relying on application metrics, blackbox exporter performs active probing from the outside in, sending requests to targets and measuring whether they succeed and how long they take. It exposes results as Prometheus metrics including probe_success and probe_duration_seconds, allowing operators to track endpoint health and response times. The exporter can be deployed as a standalone binary or Docker container and configured with a YAML file to define different probe modules for various protocols and requirements.
Teams should adopt blackbox exporter when they need to monitor external services, third-party APIs, or any endpoint where instrumenting the application itself is not possible. It suits projects that already use Prometheus and want to extend monitoring beyond internal metrics. The tool is particularly valuable for measuring probe timeout ratios against scrape intervals, helping operators understand whether their monitoring windows are sufficient. It supports TLS and basic authentication for securing the exporter's HTTP endpoints, and provides separate logging controls for application logs and prober-specific logs, allowing fine-grained visibility into probe operations.
The project receives issue reports primarily from its user base rather than from core maintainers, indicating substantial real-world adoption. Responses to issues and pull requests typically arrive within one to two weeks. Development activity centers on bug fixes, enhancements, and feature requests, reflecting a focus on stability and incremental improvement of the existing probe capabilities.
