The minimum vertical rack space per chassis should be 1 RU, equal to 1. The width between the inside edges of the mounting posts must be at least 17. As the definition states, a server rack is a multi-level furniture piece designed to accommodate telecommunication equipment, cross-countries, and termination points for transmission media. Proper sizing and layout are critical for functionality, maintenance, and scalability. Here's a practical guide based on international standards to help you design efficient and standards-compliant. Placement of your server racks and cabinets can make a significant short and long term difference. Whether creating a small or large server room. Server rack spacing refers to the standardized measurements used to mount and organize equipment inside a server rack. See Reference Perforated Cabinet.