How to Stack and Cable a Multi-Box Phone Farm Without USB Collapse

**Layout rules** - One powered USB 2.0 hub per box branch — avoid daisy-chaining consumer hubs - Label each box ID on chassis and in software groups - Keep data cables under 2 m where possible; use active extensions for long runs **Stacking** Metal chassis stack with airflow gaps. Heaviest boxes on lower shelf; network gear on separate shelf with UPS. **Migration trigger** When mirror refresh slows or Windows reports USB resource errors on 40+ nodes, plan OTG/LAN for the next box group. **Router handoff** Box and PC on same subnet; green LED = OTG/LAN mode. Router sizing: /products/network-equipment. Installation reference: /manual · OTG/LAN tutorial: /blog/otg-lan-network-setup