What is full rack colocation?

The global colocation services market grew by 13.7 per cent through the end of 2020. More and more companies are choosing to use a colocation data centre rather than holding their servers in-house.

If you’re thinking about moving your server into a colocation centre, you’ll need to determine how much rack space you’ll need. Let’s look at the different options, from per-unit colocation through full rack colocation.

What is colocation?

A colocation facility lets you rent space for your servers and other hardware. You own the equipment so you can invest in whatever type of hardware is best for your business. The colo facility provides physical space for it as well as power, physical security, and the network backbone to connect it resiliently to the internet.

The main difference from other hosting services is that you own the hardware. With traditional hosting services, you rent the server from them but you don’t necessarily have complete control over how it’s configured.

This can limit your options as well as cost more in the long term.

Differences in colocation space

Server racks get measured in terms of rack Units (U) and rack-mounted servers are designed to meet a standard size. A 1U server is approximately 19 inches wide, 36 inches deep, and 1.75 inches in height.

A “rack” is exactly what it sounds like — a rack that the servers get bolted into. They’re built to a standard size so they can house almost any brand and model of server. A typical full-sized rack contains 42U of space.

Per-unit colocation

Per-unit colocation is the smallest amount of space you can get. The most common options available at this level are 1U, 2U, and 4U.

These options are ideal for small businesses, start-ups, and anyone who doesn’t have huge resource requirements but still wants to host their server in a data centre. This gives you the benefit of the data centre’s infrastructure without having to lease more space than necessary.

Quarter rack colocation

Quarter rack colocation is a good option if you’ve got enough equipment to need more than 4U of rack space. Assuming the rack has a total of 42U, you’ll end up with about 10U in a quarter rack.

How much of that space is available for you to use depends on how the rack is configured. The spacing of the divider shelves between each rack unit uses some space and there may be other items using part of it as well.

With quarter rack colocation from Netwise, you’ll have 10U of space, which is fully segregated and lockable.

Half rack colocation

Half rack colocation segregates half of the total rack space for your use. In a 42U rack cabinet, you’ll have 20U of space to work with.

Full rack colocation

With full rack colocation, the entire rack is dedicated to your use. You can use the full 42U of space for whatever your needs might be, including:

  • Private cloud servers
  • GPUs for machine learning and/or artificial intelligence
  • VoIP equipment
  • Network storage

This also gives you more flexibility to install non-rack-mountable equipment using data cabinet shelves. For example, if you have a tower server that you want to install in your rack, it won’t necessarily be a standard U size.

Segregated Colocation vs Per-Unit

At a glance, full rack colocation (or any other size of segregated colocation) doesn’t seem that different from per-unit space. After all, if you need a full rack, couldn’t you just order 42U of space on a per-unit basis?

You could, but segregated colocation offers a few additional benefits compared to a shared rack.

First, with full rack colocation, you can lock the cabinet so only the IT personnel you approve will have access to it. With per-unit colocation, several users will likely share the same rack.

Second, you’ll have more flexibility with the equipment you install in the rack. Some devices only need 1U of rack space while others are larger and might need 2U, 3U, or more.

With a full rack, you can configure the layout any way you like to maximize your use of the space.

Full rack colocation can also be more cost-effective. A full rack doesn’t cost twice as much as a half rack so it might be the right choice even if you don’t need all the space immediately.

Finally, if you don’t need a full rack for your equipment, you might want to consider leasing the extra space to your clients or companies that you work with.

How to determine how much space you need

Figuring out how much colocation space you need is as simple as adding up the U heights of the servers and other equipment you’ll be installing in the rack. For example, if you have four 1U devices, two 3U devices, and two 2U devices, you’ll need at least 11U of rack space, plus some additional space for cable management and cooling consideration.

If your equipment needs more than 20U, full rack colocation is the only option that provides enough space. But if it needs less than 20U, you might still want to consider full rack colocation for the reasons we mentioned above.

If you work in certain industries, you might also need to consider regulatory restrictions when choosing colocation. In the healthcare or financial markets, for example, you might need to use segregated colocation to meet the compliance requirements for the security of your clients’ personal information, meaning that shared per unit colocation is not a possibility, even for a single server.

Where to turn for help with your colocation needs

If you’re looking for full rack colocation in the UK, Netwise can help. We offer a range of server colocation services ranging from 1U through full rack options.

We’ve been providing colocation services for over a decade and are one of the UK’s leading service providers. Get in touch with us today to discuss your colocation needs or to book a tour of our data centre facilities.