Several types of storage devices are used in storage networking, but by far the most important is the disk drive. If Harry Truman worked in the storage network industry, he would have said the buck stops at the disk drive. By now we have almost come to take disk drives for granted as ubiquitous gadgets that are readily available at volume discounts. The fact is, disk drive technology is as impressive as any other technology in all of IT, with amazing capabilities and physical characteristics.
In the sections that follow, we'll examine the various subassemblies that make up a disk drive, discuss the strengths and limitations of these amazing machines, and point out what they mean for storage network applications.