subject: Data Center: Learning About Physical Layout & Environment [print this page] A data center can occupy an individual room of a building, a floor or more or an entire building. Most of the equipment in a data center is often in the form of servers mounted in cabinets, which are commonly placed in single rows forming corridors between rows. These corridors allow individuals access to the front and rear of the cabinets.
Servers differ in size from 1U servers to very large freestanding storage silos that occupy a large area on the floor. Some data center equipment such as storage devices and mainframe computers are often as large as the racks themselves. This equipment is often placed right along side the racks. Extremely large data centers use shipping containers packed with hundreds of servers each and when upgrades or repairs are needed whole containers get replaced.
The physical environment within a data center is rigorously controlled:
Data centers implement air conditioning to control the humidity and temperature of the building. Thermal Guidelines for Data Processing Environments recommends a temperature between 16 and 24 degrees Celsius and a range of humidity between 40 and 55 percent. Air conditioners are necessary because the power used in a data center heats the air. Unless this heat is removed, the temperature will rise, which may cause an electronic equipment malfunction.
Modern data centers try to implement economizer cooling, which uses outside air to keep the data center relatively cool. The state of Washington currently has a couple of data centers that cool their servers using the outside air 11 months out of the year. They do not implement air conditioners/coolers, which ultimately results in potential energy savings in the millions.nnIn order to prevent single points of failure, every element of the electrical system, including backup systems, are typically fully duplicated, and servers that are considered critical are connected to the "A-side" and "B-side" power feeds. Static switches are sometimes implemented to ensure an instantaneous switch from one power supply to another in the event of power failure.
Data centers commonly have raised flooring, which is made up of removable square tiles. These provide a plenum for air to circulate beneath the floor. This benefits both the air conditioning systems as well as provides storage space for power cabling. Smaller and less expensive data centers may not have raised flooring and may implement anti-static tiles for the surface of the floor.
Data centers also feature fire protection systems, which include active and passive design elements. Data centers also implement fire prevention programs in operations. Smoke detectors are commonly installed to provide warning of a developing fire. Data centers implement fire extinguishers, sprinkler systems and clean agent fire suppression gaseous systems in order to fight fires. They also install fire walls around the data center in order to restrict fires if one begins.
Physical security also plays a large role within a data center. Physical access to the data center is often restricted to select personnel that control the mantraps and bollards. Permanent security guards and video camera surveillance are almost always present in a data center if it is relatively large or contains sensitive information. The use of finger print recognition mantraps is beginning to become a common physical security as well.
