While planning the layout for a new 42-U rack cabinet, a systems administrator must install an 8-U, 10 kVA UPS with an external battery pack (approximately 110 kg), six 2-U disk shelves, eight 1-U compute nodes, a 1-U sliding LCD/KVM console, and a 1-U top-of-rack network switch. The data center uses a hot-aisle/cold-aisle arrangement, and the administrator must follow all safety, rack-balancing, cooling, and ergonomic best practices.
Which of the following installation orders from the bottom of the rack upward BEST meets these requirements?
Disk shelves → UPS with battery pack → compute nodes → switch → KVM console (top)
KVM console (bottom) → UPS with battery pack → compute nodes → disk shelves → switch
UPS with battery pack → disk shelves → KVM console (mid-rack) → compute nodes → switch
UPS with battery pack → compute nodes → disk shelves → KVM console (top) → switch
Best practice calls for mounting the heaviest equipment (the UPS and its battery pack) at the very bottom of the rack so the cabinet does not become top-heavy and risk tipping. Placing the six 2-U disk shelves (the next-heaviest items) directly above the UPS keeps the center-of-gravity low and groups high-wattage storage devices where cold air first enters, helping cooling efficiency.
A sliding LCD/KVM console should sit roughly at a comfortable standing or waist height so technicians can operate it without bending or using a ladder. Mounting it around mid-rack also prevents it from extending too far when opened and unbalancing the rack.
The lighter 1-U compute nodes can be mounted above the console without affecting stability, and positioning the 1-U switch in the highest rack units shortens uplink cable runs while keeping the lightest device at the top.
The other layouts either put heavy equipment higher than recommended, locate the KVM at an impractical height, or mix heavier disk shelves above lighter servers, all of which violate safety or ergonomic guidelines.