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|Up and coming|
The following technologies are heating up, but are not quite ready for enterprise storage shops.
Emerging technology is risky. The vendors are often startups and the technology isn't battle tested. But if it will solve your storage problem, it could be worth the risk. "We were a little nervous," about buying a storage encryption appliance from Neoscale Systems Inc., admits Kevin Granhold, director of server and desktop services at the University of Texas Health Sciences Center, in Houston. The vendor was small and the technology was new.
But Granhold's group believed the benefits outweighed the risks. The Health Sciences organization stores large amounts of patient and research data. As a result, it faced several data privacy issues relating to HIPAA and various internal policies. After looking at the usual access and privacy-control products, it chose Neoscale's encryption appliance. "It was cheaper and easier to encrypt it all than to deal with different policies and procedures for the various data," Granhold says.
The emerging technologies discussed here include continuous data protection (CDP), intelligent storage switches, storage encryption, network-attached storage (NAS) accelerators and storage virtualization. Several other storage technologies are equally interesting, but are currently in earlier phases of the adoption cycle. These include grid storage, serial-attached SCSI (SAS) and InfiniBand (see "Up and coming" on this page).
Continuous data protection
CDP--also referred to as continuous backup--are products that track and save information about stored data changes. (See "Nonstop data protection".) In the event of a failure or data corruption, the CDP system can return to any point in the past, usually just before the storage failure or data corruption. Some CDP vendors include Mendocino Software, Revivio Inc. and XOsoft Inc. The field is becoming crowded, and larger vendors haven't weighed in yet, although they're starting to make noises.
"We are big advocates of CDP. We think it is the future of data protection," says Nancy Hurley, senior analyst at Enterprise Strategy Group. The reason: Despite decades of work on the problem, "backup is still the No. 1 headache," she says. CDP promises to eliminate that headache once and for all. In a survey of buying intentions by TheInfoPro, roughly half of the 90 managers who responded to the survey either had purchased CDP technology or plan to do so by 2006.
Each vendor does CDP a bit differently, but the basic approach is to record every change to the stored data. You're essentially making a journal or index of the changes that are time-stamped when they're entered. When you need to restore data, you just restore, or rewind, to the point in time you want to recover.
CDP differs from point-in-time snapshots in three ways. First, you don't have to halt activity as you do with snapshots. Second, you aren't storing the changed data like snapshots, so you don't need as much disk storage. Third, you can restore to any point in the past, unlike snapshots, which are taken at specific intervals.
"Right now, companies are doing multiple hot mirrors and snapshots on their most expensive disk arrays to try to get the same result. Why bother when you can replicate block I/O actions to a free-flowing journal and go back to any point in time?" asks Jon Toigo of Toigo Partners International.
Compulinx Managed Services Inc., White Plains, NY, came to a similar conclusion. The company operates as a managed service provider with 70TB of storage spread across what Terrence Chalk, CEOof Compulinx, describes as four class-A data centers. Customer data is replicated among the data center storage area networks (SANs) for disaster-recovery purposes.
To ensure high availability, Compulinx made XOsoft's CDP capabilities part of its service offering. Using itself as the test subject, Compulinx ran XOsoft's Data Rewinder on a subset of its 250 servers at multiple facilities. On two occasions, service went down. "We were able to very quickly get everything back up using Data Rewinder," says Chalk. Since then, the company has been using CDP as a standard service for its high-availability customers. "It became clear that we don't need tape. With XOsoft, we can recover the data faster," he adds. The company has been without tape backup for more than six months.
How hot: heating up fast.
Risk factor: medium, because the technology may fail to scale, either in the volume of data it can handle or the performance it delivers.
Buy or pass: If you need the ability to recover current data fast, go for it.
This was first published in October 2004