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Server Racks: Server Racks How and Why To Use

A 19-inch rack is a standardized (EIA 310-D, IEC 60297 and DIN 41494 SC48D) system for mounting various electronic modules in a "stack", or rack, 19 inches (480 mm) wide. Equipment designed to be placed in a rack is typically described as rack-mount, a rack mounted system, a rack mount chassis, subrack, rack mountable, or occasionally, simply shelf. The slang expression for a subrack (generally 1U = 1.75 in = 44.45 mm height) is "pizza box" due to the similarity in size and shape, see also pizza box form factor. Most racks are sold in the 42U form: that is, a single rack capable of holding forty-two 1U pizza box servers, or any combination of 1U, 2U, 3U or other height units that add up to 42 or less. See Rack unit. Because of their origin as mounting systems for railroad signaling relays, they are still sometimes called relay racks, but the 19-inch rack format has remained a constant while the technology that is mounted within it has changed to completely different fields. This standard rack arrangement is widely used throughout the telecommunication, computing, audio, entertainment and other industries, though the Western Electric 23-inch standard, with holes on 1-inch centers, prevails in telecommunications. In 1965 a durable fiber reinforced plastic 19-inch rackmount case was patented by ECS Composites and became widely used in military and commercial applications for electronic deployment and operation. State-of-the-art rackmount cases are now also constructed of thermo stamped composite, carbon fiber and DuPonts Kevlar for demanding military and commercial uses. 19-inch racks are often used to house professional audio and video equipment, including amplifiers, effects units, interfaces, headphone amplifiers, and even small scale audio mixers. They are also widely used for computer server equipment, allowing for dense hardware configurations without occupying excessive floorspace or requiring shelving. A third common use for rack-mounted equipment is industrial power, control, and automation hardware, typically in 46U racks. Typically, a piece of equipment being installed has a front panel height 1/32-inch (.031") less than the allotted number of Us. Thus, a 1U rackmount computer is not 1.75-inches tall but is 1.719 inches (43.7 mm) tall. 2U would be 3.469 inches (88.1 mm) instead of 3.5-inches. This gap allows a bit of room above and below an installed piece of equipment so it may be removed without binding on the adjacent equipment. server rack, server racks, rack servers, 1u server rack, server rack mount, 1u rack servers, 1u server racks, server rack cabinet, 2u rack server, computer server rack, rack mount servers, discount server rack