#iptables

When a Docker Service Looks Healthy but Times Out Externally: Uptime Kuma, WARP, and Return-Path Routing

A write-up of a deceptively tricky infrastructure issue: the container health check was green and the port was published, yet Uptime Kuma still reported the service as down. The real root cause was not the app, but Cloudflare WARP changing policy routing so Docker replies left through the wrong path.