Every IT pro that I know of has several of the same fears: Internet outages, being unable to restore from a backup, servers not coming back up after maintenance, and so on. One other item that often makes the list but fortunately doesn't occur too often is a power outage. Still, the threat is ever present and almost always happens without any warning whatsoever.
Most organizations solve the power outage problem by installing an Uninterruptable Power Supply (UPS) -- a backup battery. In the event of a loss of electricity from the local power company, the UPS takes over nearly instantaneously, so the computer that's protected by the UPS isn't impacted at all. As you can see in Table 1, there are many vendors that offer UPSs. You'll find that the vendors offer a wide gamut of protection, from a single desktop computer UPS all the way to a site UPS that can protect an entire data center and remotely shut down equipment if necessary during an extended power outage.
Things to Consider When Designing a Power Protection Solution
Although it might be tempting to simply purchase the largest UPS you can afford and plug everything into it, some due diligence will help your wallet. For example, if you have a generator in addition to a UPS, consider how long you'll have to run on the UPS before the generator will be able to take over. You also need to consider how long you'll need to shut everything down if the generator doesn't start for some reason and you remain on UPS power. It's also helpful to include some client machines (such as those used by the IT administrator and key operations personnel) in any power protection design. Don't forget about networking gear either -- you don't want to fall off the Internet or have your telephones stop working, especially if you have VoIP phones that utilize Power over Ethernet (PoE).
Things to Consider When Selecting a UPS
There's plenty to consider when selecting a UPS. After determining the type of UPS (online, line-interactive, or standby) needed, the prime consideration is almost always the runtime available when running on battery. If you find a vendor and model line you're happy with but need some extra battery runtime or are concerned about future growth, check with the vendor to see if they offer a battery expansion module. In some cases, these modules can extend the battery runtime by an hour or more.
Other important considerations include the number of available battery-backed outlets versus the number of surge-only protected outlets, the input voltage and amps, and the input plug type. You won't be able to connect a 240-volt UPS to an ordinary NEMA 5-15 receptacle, for example. Likewise, if your UPS is site-based and not a tower or rack-mount model, you'll need a qualified electrician to install the unit. You'll certainly want to be able to connect to your UPS through management software, so pay particular attention to the type of connectivity the UPS offers (e.g., serial, USB, Ethernet) and if the vendor includes management software or if it's a separate purchase.
Finally, don't neglect the "little" details -- the UPS unit's dimensions and weight. Not only will you need to know if the unit will fit in whatever space you've chosen for it, you'll want to leave some workspace around the unit in the event it needs to be serviced for battery replacement, air filter changes (if necessary), and so on.
Maintenance of your power protection equipment is important. UPS batteries need to be tested regularly and replaced every three to five years. If you have a larger unit that requires other upkeep (e.g., air filter changes), you need to make sure those maintenance items are taken care of. If you have a generator, don't neglect it in favor of the UPS or vice-versa. Ideally, your power protection solution will automate the transfer from utility power to UPS power to generator power back to utility power, so you'll want to ensure that all of the components required for that to happen are well-serviced.
Although power outages are rare in the United States, Murphy's Law will ensure that the power goes out at the most inconvenient time, such as 4:00 p.m. on a Friday or 2:00 a.m. on a Sunday. A well-designed, reliable, and tested solution that includes quality UPS hardware will mean you only receive a few text messages informing you that your backup power is on and functioning, keeping all your critical data and systems safe.