Storage gets smarter

Intelligence is moving into the storage fabric, but smart storage like this might only make sense for the biggest, most complex SANs.

Remember when cutting storage costs and administrative headaches simply meant implementing a storage-area network? Those days are gone. Now storage heavyweights Brocade Communications Systems and Cisco are pushing a new panacea - moving storage intelligence off SAN servers and storage devices and into the SAN fabric itself.

Although more intelligent SAN switches and appliances promise easier management and better scalability, the trick for network executives will be to make the move cost-effective, users and analysts say.

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How it works Make the move judicious Switch or appliance? Look at partnerships The acquisition game What to ask your switch vendors

Remember when cutting storage costs and administrative headaches simply meant implementing a storage-area network? Those days are gone. Now storage heavyweights Brocade Communications Systems and Cisco are pushing a new panacea - moving storage intelligence off SAN servers and storage devices and into the SAN fabric itself.

Although more intelligent SAN switches and appliances promise easier management and better scalability, the trick for network executives will be to make the move cost-effective, users and analysts say.

"Not everyone will be able to take advantage of this move to put more storage intelligence in the SAN fabric," says Tom Barclay, lead developer and program manager for the TerraServer project, which provides interactive U.S. Geological Survey aerial maps to users via the Web. "It will make sense only for the biggest, most complex SANs."

Vendors agree. "You won't think about moving intelligence into the fabric until you have a very large SAN in place, with a very large amount of servers, disk drives and arrays," says Tom Buiocchi, marketing vice president at Brocade, which comes by its intelligent storage switch technology via the November 2002 acquisition of start-up Rhapsody Networks. "At that point, it becomes crucial."

The key is making sure that not only are you saving management costs, but that you move the right applications to the fabric and that you can recoup your investment in other intelligent devices within the SAN.

How it works

In traditional SANs, the intelligence necessary to perform key storage applications such as virtualization, snapshot copying, data replication and disk mirroring are performed primarily at the host, or server, level.

This means that to implement virtualization, in which servers view all enterprise storage devices as one large pool of storage, the virtualization software must run on every server.

"Say I have 100 servers across my company, and 25 are from Dell running NT, 25 are from Sun, 25 are from IBM and 25 are from HP," Buiocchi says. "If I want to do virtualization today, typically I buy software and load it on all my servers." That's 100 licenses, with some for NT, some for Solaris and so on, he says.

The result is 100 management touch points for the storage administrator, who needs to track and maintain what the servers are running. But what if you could move that same piece of software off those 100 servers and on to one or two SAN switches?

"It's essentially the same software customized to run on a switch as opposed to a server," he says. "And now you've reduced that management toll to one or two touch points."

You've also opened up the storage to gain a many-to-many relationship, analysts say. "Usually, when storage is tied to the server or host, SAN users with access to that host can reach only the one storage device attached there," says David Hill, vice president of storage research at Aberdeen Group. "But when you move that functionality out to the switch, now many users have access to many hosts and storage devices. It scales up the storage environment."