Network Loop Detector with W5500 and ESP32

Network loops can paralyze an entire infrastructure in seconds. To prevent this, I developed a standalone hardware diagnostic tool using an ESP32 and dual W5500 Ethernet controllers. The biggest challenge in development was the "Zombie Socket" phenomenon: when an upstream L2 switch detects a loop and temporarily shuts down the port, the W5500 hardware socket is forced into a "Closed" state. Even after the link is restored, the tool would remain silent. This project implements a custom "Self-Healing" state machine in Rust that monitors the W5500 registers in real-time. It detects the zombie state and re-binds the UDP socket within milliseconds, ensuring 100% recovery from network port blocks. Key Features: - Zero-config deployment using APIPA (169.254.x.x) - OS-bypass: Direct SPI control of dual W5500 stacks - Real-time loop detection via MAGIC UDP probes - Industrial-grade reliability with automated socket recovery Source Code (GitHub): https://github.com/t13801206/esp32-loopchk Made with Google Vids https://vids.new/ #MadeWithGoogleVids #ESP32 #RustLang #W5500 #Networking #OpenSourceHardware #EmbeddedSystems