Where NAS hasn't gained traction, at least not yet, "is for massive storage consolidation or to consolidate [block-level] enterprise application storage," says Foskett. Application consolidation remains the province of SANs. "A few companies I know are using NAS for database access, but they are just mounting it via NFS or Windows over CIFS [the Common Internet File System]," says Foskett. "It's a little like hammering a nail with a screwdriver. They do it because they can have many clients accessing the same data. They like the NAS interface, and performance isn't critical to them."
Server consolidation
Consolidation lowers costs by enabling centralized management. Chicago's Field Museum is typical: "We had multiple small servers with about 1TB of storage. It was unmanageable. So, we consolidated seven file servers on one NAS box," says Neil Young, manager of the museum's application and enterprise services group. Even large servers get maxed out and can't expand further, "but with NAS, we can just keep expanding as needed," he adds.
Except for the low end, NAS devices can consolidate many servers. "The filers can handle a lot if they are not swamped by client requests," Foskett explains. The limiting factor isn't the number of consolidated servers, but the volume of user traffic. Other storage managers report finding 10:1 file server consolidation is reasonable. With Citrix servers, the ratio is 6:1 due to greater client traffic. Dell Computer Corp. suggests a 5:1 to 8:1 consolidation ratio.
| How NAS fits into different storage environments |
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