What problem does it solve? When an RDK board becomes unreachable over SSH, ping, or WiFi, developers lose all remote access and cannot continue device-side work. This Skill performs layered on-board network diagnosis (interface, link, IP, route, gateway, DNS, SSH service) and provides official fallback login paths such as serial console and static IP defaults. ## Core Features & Use Cases - Layered Network Self-Check: Runs scripts/net_diag.sh on the board to inspect interfaces, link state, IP addresses, default route, gateway reachability, DNS resolution, and SSH service status, reporting the first failed layer as structured JSON. - Official Fallback Paths: Provides board-specific serial console baud rates (X3 921600, X5 115200), default static IPs (192.168.127.10/24), and VNC guidance sourced from official D-Robotics documentation. - Use Case: A user reports "ssh 连不上开发板". The agent runs net_diag.sh on the board, finds first_failed_layer is "gateway", and guides the user to verify the router, or falls back to serial login at 115200 baud when the board is fully unreachable. ## Quick Start Ask the agent to run the network diagnostic script on your RDK board and explain why SSH is not connecting.