A rack is where power, cooling, cabling and IT all meet.
Every other layer converges at the rack: power arrives through rack PDUs, cooling is directed by containment, cabling is dressed into the cabinet, and the IT itself is mounted in rack units (U). Decisions made here ripple across the whole facility, so racks deserve more thought than they usually get.
What to specify
- Height — 42U is standard; 45U and 48U squeeze more density where ceiling height allows.
- Weight rating — loaded racks are heavy; static and dynamic load ratings matter.
- Airflow — perforated doors and correct front-to-back airflow are essential for cooling.
- Depth and width — deep servers and side cable management need the right dimensions.
- Containment-ready — plan rows for hot/cold aisle containment from day one.
Rack PDUs & cable management
Inside each rack, rack PDUs (RPDUs) distribute power to equipment; metered and switched versions let you monitor and control consumption per outlet — vital for capacity planning and colocation billing. Good vertical and horizontal cable management keeps airflow clear and maintenance sane.
| Brand options | Rittal, Schneider (APC), Vertiv, Legrand, Eaton, Netrack, Valrack |
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How it scales
| Small | A handful of standalone 42U cabinets, basic PDUs. |
|---|---|
| Medium | Rows of racks with containment and metered PDUs. |
| Large | Standardised rack rows, full containment, switched PDUs integrated with DCIM. |
Frequently asked
42U, 45U or 48U — which should I choose?+
42U is the safe standard. Go higher only if ceiling height, floor loading and cooling airflow all support the extra density.
Do I need metered PDUs?+
For capacity planning or colocation billing, yes — per-rack (or per-outlet) power visibility is extremely valuable.
Can I add containment later?+
You can, but it's far cheaper and cleaner to plan rows for containment from the start.