Small business networks are rarely planned. They grow: one router from the provider, then another switch as computers are added, then a CCTV recorder, then a second access point. A few years on, everything is piled in one corner with cables whose ends nobody knows any more.

The problem is not appearance. When something fails, nobody knows which cable goes to which room. Equipment gets kicked, unplugged, or overheats. A network rack solves all three.

When you need a rack

The signs are fairly clear:

  • There is more than one switch, or a switch with more than 16 ports in use.
  • There is a CCTV recorder, NAS, or small server running constantly.
  • Equipment sits on the floor, under a desk, or where people walk.
  • During a fault, it takes a long time to find the cable in question.

Homes and offices with one router and a few devices don't need one.

Reading the sizes

Almost all network racks use the 19-inch width standard, so equipment from different brands fits together. Two dimensions need choosing:

  • Height, in U. One U is about 4.45 cm. Count the equipment you have, then add at least half again for airflow and growth. A rack full on day one is too small.
  • Depth. Wall racks are often only 45–50 cm deep. Some CCTV recorders and NAS units are deeper. Measure the deepest device before buying.

Home routers and switches that aren't rack-shaped can still sit on a shelf mounted inside.

Wall rack, floor rack, or open frame

  • Closed wall-mounted rack. The most common choice for small offices and shops. A locking door keeps curious hands out, and it uses no floor space. Make sure the wall can bear the weight, plasterboard cannot.
  • Closed floor-standing rack. For a small server room with a large UPS, several servers, or many switches.
  • Open frame. Cheapest and easiest to cool, but only suitable in a locked, dust-free room.

Heat

A closed cabinet holding equipment that runs 24 hours can get much hotter than the room around it. A few things help:

  • Choose a cabinet with an exhaust fan at the top, and make sure the fan is actually switched on.
  • Leave one empty U between hot devices.
  • Don't put the cabinet in an unventilated storeroom or in direct sun.
  • Don't stack things on top of the cabinet so its vents are covered.

Signs of overheating are covered in the guide to hot routers and cooling them.

Cables and labels

A tidy rack without labels just moves the mess somewhere nicer. What makes the difference:

  • A patch panel. Cables from the rooms terminate on the patch panel, then connect to the switch with short leads. Long runs from the walls are no longer tugged every time something changes.
  • Labels at both ends. The patch panel port number matches the number on the wall socket.
  • Short coloured leads. For example one colour for CCTV, one for access points.
  • A simple chart inside the cabinet door: which port goes to which room.

Power deserves attention too. A rack power strip (PDU) with protection beats ordinary extension leads daisy-chained together, and is better still when fed from a UPS.

What to do

Use a rack once there is more than one switch or always-on equipment. Choose a height with spare room, measure the deepest device, manage heat with a fan and spacing, and label both ends of every cable. Those labels are what turn the next fault into minutes rather than hours.

Frequently asked questions

What do 6U, 9U, or 12U mean?

U is a rack height unit, about 4.45 cm. A 9U rack holds equipment nine units tall in total, for example a 1U patch panel, a 1U switch, a 1U router, a shelf or two, and spare room for airflow and growth.

Is a wall-mounted rack enough for a small office?

For an office of up to a few dozen people with one or two switches, a 6U–12U wall rack is usually enough. A floor-standing rack is only needed with servers, a large UPS, or lots of equipment.