If you're like me, you've probably tried at one time or another to drive a nail with the flat side of a wrench or attempted to remove a bolt with a hammer. If you haven't, I'm here to tell you: Don't do it. Listen to my grandfather, who was perhaps a little too fond of the cliche: Use the right tool for the job.
Sometimes, the right choice is not so obvious. Confusion reigns, for example, about the best applications for NAS appliances in the enterprise -- and how they compare to SANs. Adding to that confusion are a growing number of devices that offer both NAS and traditional SAN capability in the same box. As you build your organization's storage strategy, it's important to understand the distinction between the two.
As they say: Never bring a NAS to a SAN fight (or vice versa).
Drawing the line between NAS and SAN
If you know a little about enterprise storage, you probably understand the conventional distinction between NAS and SAN: A NAS device works at the file level, while a SAN operates at the block level. File systems organize raw blocks of binary data in such a way that you can create identifiable files with human-recognizable names. Depending upon the file system in use, a NAS also lets you perform more advanced tasks, such as enforce security constraints, specify usage quotas, perform file indexing, and the like. From there, your operating system (or your NAS appliance's operating system) allows those files to be shared on the network for clients to access.