In this article, let us look at some basic information about a network rack – we’ll see what a network rack is and why it is required, the two types of network racks – wall mounted and floor standing, and a short note on the various accessories that might be useful with a network rack.
What is a Network Rack?
A Local Area Network (LAN) is comprised of multiple networking equipments like network switches, routers, UTM appliances, Servers, patch panels, cables, modems, etc. These equipments are generally kept inside a network rack, which is a closed or open enclosure that can hold them. The size occupied by networking hardware equipments follow certain industry standards so that they could fit in to the network racks, which too follow those standards. The common width of a network rack (and the networking equipments) is 19″ (Inches) – most of the racks are made to accommodate any equipment that can fit in to this space. Also, the networking equipments have fixed heights that are mentioned in terms of Rack Units.
1 Rack Unit (RU) = 1.7 inches / 4.4 cm.
So, if a networking equipment is specified as 2U, then it has a height of 3.4 inches (approx). So, if one has the sizes (In RU) of all the networking equipments that needs to be placed in a rack, the required height of the Rack (in RU) can be easily calculated as the sum of the heights of all the individual equipments – generally slightly more than that, in order to accommodate the networking equipments freely in the rack and also to provide for future expansion.
Why are Network Racks required?
Network Racks are an important component of the structured cabling system.
Network racks are required for neatly, efficiently and safely holding all the networking equipments. If there are no network racks/ patch panels, then the cabling would look cluttered. Network racks can hold many components in a relatively smaller space, which enables one to utilize the available storage space very efficiently. Network racks are required for the physical safety of all the equipments kept within, as most of them could be locked and access denied for unauthorized personnel.
Network racks are also required for improving the health of the networking equipments stored inside. For example, when the cables are taken carefully and neatly through the cable managers in the racks, there is little chance of data loss due to excessive cable bends. Also, the cooling fans in the network racks provide additional cooling to prevent any damage to the networking equipments kept inside them, due to over heating.
Wall Mounted Network Racks:
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- Wall Mounted Network Racks are useful for housing edge devices in individual departments with fewer networking equipments.
- Common sizes: 6U, 9U, 12U, 15U.
- The front panel generally has a hardened glass door to view they equipments inside clearly and also has a lock to ensure physical security.
- There are two common types of wall mounted racks – Single Section Racks, which have one glass door in the front, that can be fully opened and the cable entry/exit is via the holes in the top and bottom of the racks & Double Section Racks, which are like the single section racks but have an additional opening behind the rack (actually, a rear panel is fixed to the wall, and the whole rack is fixed to one side of the rear panel firmly, and can be turned front/ back to enable one to open and view the rear side of the rack).
- Network Racks are generally made up with steel body (sometimes with aluminum enclosures) with powder coated paint finishes.
- Network Racks generally have provisions for ventilation in the top/bottom/sides through vents/ holes.
- They contain some accessories as well, which is discussed in the last section of this article.
Floor Standing Network/Server Racks:
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- The Floor Standing racks are used to house both network as well as server equipments. These are primarily used in data centers and other places with a large number of equipments.
- Most of the points that are applicable to the above wall mount racks are applicable to floor standing server racks as well, except that these are bigger and kept on the floor (some might even have wheels attached, to enable their movement).
- Common sizes: 24U, 30U, 36U, 42U, 45U.
- The whole front section generally comes with full length doors with hardened glass/ lock. Some might even have rear doors.
- In addition to the normal cable managers, these floor standing racks also offer specialized channels for electrical cabling, network cabling, etc which ensures neat movement of cables in the rear end, along the height of the racks.
- These racks can house more equipments and can handle loads of around 450-500 Kg.
- Floor mount racks are supplied either in CKD (Completely Knocked Down) condition where individual components are shipped to the site and the rack itself is assembled in the site (or) is assembled in the factory and shipped as a whole.
Network Rack – Accessories:
- Fan Housing Units: These are either mounted in the roof (or) in the side plate. Each unit generally consists of 2/4/6 fans that are used for cooling the equipments inside the racks. Some vendors also provide rack mounted fan housing trays that can be mounted along with other equipments in the rack to provide cooling at specialized places.
- AC Distribution Box: Network racks generally consist of a lot of equipments that need AC power. It would be inconvenient if each unit needs to be powered from an external source separately. So, an AC distribution box is used inside the rack to give power to individual equipments using one or two power lines from outside. The AC distribution box generally consists of 5 to 15 sockets (5A/15A).
- Cable Manager: A cable manager is generally an open conduit (with metal holdings) for passing multiple cables across the horizontal section of the rack. This makes the cabling arrangement look neat as well as prevent any excessive bending of the cables.
- Fixed/ Sliding Shelves: Not all the equipments that need to be kept in a network rack are rack mountable. Some of them come in different shapes and sizes. So, a fixed shelf plate is inserted in to the rack and these equipments are kept over it. For example, the standing desktop based servers can be kept over the shelves. There are certain heavy duty shelves to accommodate higher weight equipments. There are some sliding shelves which can be used to pull out equipments placed on them for say, frequent servicing.
- Additional cable channels and conduits enable easier and neat arrangements of cables.
- Modem holders: Some vendors provide special chassis type shelves in order to hold more number of modems vertically, one next to another. Otherwise, they are kept horizontally and each shelf can hold only a few of them, which results in inefficient usage of rack space.
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