Disaster recovery: Know what you really need

作者： Stephen Simpson

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[ 2004-06-17 18:57 ]

It would be easy, particularly these days, to be swept up in a frenzy of disaster recovery (DR) implementation. But look before you leap, experts advise. Do enough planning, at enough levels of the company, to know what your business really requires to keep running. And be brutally honest about whether you can devote in-house resources to the issue or if you should look around for someone else to manage the process for you.

Also, don't think about this as purely a technical issue. Sure, technology plays a key role in your ability to capture and recover business-critical information. But disaster recovery is just one piece of an overall contingency plan.

"Disaster recovery is just one extreme example of business continuance," to make sure the business is up and running no matter what, says John Webster, a senior analyst at Illuminata Inc. in Nashua, N.H. A business can be interrupted by an all-out disaster such as a hurricane, or it can be brought to its knees by human error -- someone corrupting a database either accidentally or on purpose. A business has to be ready for anything, man-made or natural, catastrophic or relatively minor, Webster says. The vast majority of things that take systems off-line fall into the category of human error, he adds; unplanned down time generally is not due to a disaster.

The first step toward a good DR plan is to be absolutely sure which data really is critical to keeping the business going. Know the types of data you've got and which would really be a loss if they were gone. The key here is to get high-level buy-in from around the corporation, so that the IT group isn't guessing about what's important.

Then take a look at how you might want to back up and recover that data. Technologies to choose from here include data mirroring (taking a copy of the data as it is created in real-time, such as with RAID), hot backup (copying real-time data and storing it on a server at a different facility) or taking a snapshot at intervals of every five minutes, every hour, or every 24 hours.

Or you might opt for all of these approaches for different applications, for different reasons. As Webster says, "look at your application base, determine how much money you want to throw at this problem, and then go after shoring up your most critical resources first."

One of the fine lines to walk here is backing up enough information, but doing it in such a way that doesn't disrupt your everyday operations, says Jamie Gruener, an analyst at the Yankee Group in Boston. "Different data have different performance requirements," he says. You need to assess what all this will mean to existing storage devices, networks and applications if you start mirroring applications or doing hot backups.

Another issue can be the time it takes to actually recover the data. Storage-area networks, for example, are wonderful tools for storing information, but they can be less efficient at actually finding the stored data.

The make-or-buy decision comes down to two essential factors: how many internal people can you afford to dedicate to DR planning and implementation? And how much money will you really save by going outside? If yours is a small IT group, it might be worth it to pay an outside consultancy to come in and set up your DR plan, policies and procedures and then train your internal folks to handle things from there.

Other outsourcing alternatives include the traditional DR services firms, like IBM and Comdisco, which will handle everything from data backup and restoration to making sure you've got copies of your major applications and all the hardware you need in case of a flood, for example. Or you might go with a storage-services provider like NaviSite, Storability, StorageNetworks or WorldStor. These handle storage specifically, in which case you'll get an expert in storage and data backup. So the tradeoff is depth vs. breadth, in many cases.

Whatever you do, make sure you buy only what you absolutely require. DR is "like insurance," says Dan Tanner, an analyst at the Aberdeen Group Inc. in Boston. "You have to judge what you need and pay for only what you need. There are a lot of hucksters out there who will try to sell you more than you need."

More on this topic:

SearchStorage has a collection of links about Disaster Recovery, as well as sections on Backup and Data Recovery.

SearchDatabase includes extensive links to resources on Backup and Recovery.