UNIX System Administration Handbook - Evi Nemeth [445]
You might want to consider putting your servers and network infrastructure equipment on an Uninterruptible Power Supply (UPS). Good UPSs have an RS-232 interface that can be attached to the machine to which they supply power. This allows the UPS to warn the computer that the power has failed and that it should shut itself down cleanly before the batteries run out. We’ve had fantastic luck with UPSs manufactured by BEST Power Technology. They’re not the least expensive, but they are very nice products.
One study has estimated that 13% of the electrical power consumed in the United States is used to run computers. Traditionally, UNIX boxes were based on hardware and software that expected the power to be on 24 hours a day. These days, only servers and network devices really need to be up all the time. Desktop machines can be powered down at night if there is an easy way for users to turn them off (and you trust your users to do it correctly).
See page 33 for more information about shutdown procedures.
At the very least, ask users to turn off monitors and laser printers when they go home; these are the biggest power hogs. When buying new equipment, look for an Energy Star certification. It signifies that an item complies with EPA guidelines for energy-efficient operation. For example, Energy Star monitors must be able to automatically shut off their displays after a certain period of inactivity.
Remote power control
You may occasionally find yourself in a situation in which you have to regularly power-cycle2
a UNIX server because of a kernel or hardware glitch. Or perhaps you have non-UNIX servers in your machine room that are more prone to this type of problem. In either case, you may want to consider installing a system that will allow you to power-cycle problem servers by remote control.
One inexpensive and popular solution is the X-10 power control system, which includes a box that will answer a phone line and will power-cycle machines based on touch-tone codes. The basic X-10 product line is described and sold on-line at the site www.x10.com. If you’re really serious about this approach, be sure to check out what’s available at www.smarthome.com, which primarily focuses on home automation but includes higher-quality X10-compatible gear.
A more deluxe (and expensive) solution is manufactured by American Power Conversion (APC). Their MasterSwitch product is similar to a power strip, except that it can be controlled by a web browser through its built-in Ethernet port. You can reach APC at (401) 789-0204 or on the web at www.apcc.com.
24.9 Racks
Much to the dismay of the folks on Wall Street who once viewed raised floors as a corporate status symbol akin to owning a Lamborghini, the days of the true raised-floor machine room are over. Have you ever tried to trace a cable that runs under the floor of one of these behemoths? Our experience is that while it looks nice through glass, “raised floor” is a synonym for “rat’s nest.” If you must put in a raised floor, use it to hide electrical power feeds and nothing else.
If your goal is to operate your computing equipment in a professional manner, a dedicated machine room for server-class machines is essential. A server room not only provides a cozy, temperature-controlled environment for your machines but also addresses their physical security needs.
In a dedicated machine room, storing equipment in racks (as opposed to, say, setting it on tables or on the floor) is the only maintainable, professional choice. Today, the best storage schemes use racks that are interconnected with an overhead track system for routing cables. This approach provides that irresistible high-tech feel without sacrificing organization or maintainability.
The best overhead track system is manufactured by Chatsworth Products (Chatsworth, CA, (818) 882-8595). Using standard 19” single-rail telco racks, you can construct homes for both shelf-mounted and rack-mounted servers. Two back-to-back 19