Resilience & Health Checks

Iron-Proxy is designed to assume that upstream networks are hostile and backend servers will inevitably fail.

Active Background Probing

A dedicated Tokio task runs outside the proxy engines, firing HTTP GET requests or TCP pings at the configured interval.

• If a backend fails to respond within the strict 2-second timeout, the DashMap registry instantly marks the node as Dead.
• The routing engine will immediately cease sending new connections to that node.
• The probe continues pinging; once the node returns a successful response, it is automatically reintroduced to the cluster.

Passive L7 Circuit Breaking

If the active probe hasn’t detected a failure yet, but the L7 proxy engine encounters an unexpected socket drop or 502 Bad Gateway from a backend, the L7 proxy acts defensively. It automatically retries the buffered request on another node, and proactively flags the failing node as Dead in the shared registry.