What’s the difference between server rack rails and server rack mounting rails

There are a number of variations of server rack shelves and rails. This can often be confusing for the consumer, making it difficult to assess which might be the best option for your own specific needs. 

In particular, a key question is whether you opt for a server rack shelf or server mounting rails. The key factor in the decision you make is what you will be using them for. Rails are generally used for equipment that’s built to be mounted on a rack, while shelves can be more versatile. 

Let’s take a look at each of these options in more detail to help inform your choice.

What is a server rack shelf and what is it used for?

A server rack shelf is a form of shelving that’s specifically designed to be mounted into a server rack, AV racks and network racks. It can be used with a wide variety of hardware components. This might include servers, desktop PCs, tools, switches, monitors, printers and other equipment. 

Server rack shelves are designed and constructed to store a range of IT equipment with the rack shelf being mounted directly inside a server rack. This means that the server rack shelf will take its place alongside other rack mounted equipment, providing additional storage and helping to keep your equipment better organised and easier to service.  

There are a variety of different types of shelves, each with different advantages and disadvantages. Some shelves are fixed or static, others can be slid in and out of the rack. The latter can make servicing and repair simpler as they allow for better access to the equipment. Other types of shelves are available, such as the 2-post or cantilever mounted which are frequently used for telecommunications racks. 

To help maximise airflow, rack shelves will frequently be vented. This can provide additional airflow helping to keep the equipment working and less prone to failure. 

Standard server rack shelves come as fixed or slide models. Fixed shelves come in a number of different variants. 2-post cantilever shelves are usually small and are ideal for lighter equipment such as switches. 

4-post shelves are stronger, making them suitable for heavier items such as desktop PCs and printers. 4-post shelves can be more adaptable than 2-post shelves and can be used for a wider variety of different uses. 

If you have heavy equipment that you need to access easily, then sliding shelves may be more appropriate. 

What is a server rack mounting rail and what are its uses?

Rack mounting rails are designed to mount and secure servers and other IT equipment in a safe, efficient and space saving manner. Server specific rails don’t act like a shelf in supporting equipment from the bottom. Instead, they use pins in the server chassis, known as shoulder screws. These lock into the J-slots in the rail, preventing movement and supporting the weight of the equipment. 

Server rack mounted rails are available in both fixed and sliding variants. Fixed rails are stationary which means that the server can only be removed if there’s room above the rail from which to access it. A fixed rail will usually be cheaper but will mean that your access is to some degree more limited. 

Slide rails give you more flexibility. They consist of two separate rails; one being attached to the server, the other attached to the rack. These can be more costly initially but make maintenance more straightforward. Routine repairs and maintenance can usually be completed without the need to detach network cables. 

Universal rails are shelves that hold the edge of servers and other equipment. They can hold any type of server as long as the equipment fits its particular dimensions. Unlike a fixed rail, universal rails don’t have to be locked. This means they can slide out for easy maintenance. It’s worth bearing in mind that the only means by which they can be secured, however, is by using thumb screws.

Do I need a server rack shelf or a server rack mounting rail?

If you’re mounting a server, then in most cases a server rack mounting rail is preferable for a variety of reasons. It’s usually a more intelligent use of space, as well as a cost-effective option. For most other equipment, a shelf will frequently be the most practical option. If you have space available on a pre-existing shelf and want to house a server, it won’t do any harm to use the shelf space to save money.

If you opt for a shelf the key question will be whether you should use a sliding or fixed shelf. In a situation where you need regular access to the equipment, a sliding shelf will generally be your best option. This is particularly applicable if the equipment is heavy. 

If, on the other hand, you’re using your shelf for small pieces of equipment that can easily be lifted, perhaps with just one hand, a fixed shelf will usually be adequate. 

In short, a server rack mounting rail is generally a more fixed and less flexible form of storage for items that require less daily access and general maintenance. They offer more security, making them ideal for servers. 

A server rack shelf is a more adaptable solution but offers less in terms of security. Often both options will be used together, offering a combination of flexibility, access and security in equal measure with a configuration that suits particular requirements.

Get in touch

AT-GBICS stock a comprehensive range of Rackmount equipment from leading manufacturers at competitive prices. To discuss your particular requirements, call +44 1202 424518 or email us via our Contact Page.


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