MAID was born from the simple idea that not all storage is the same. “Mission critical” data best earns its keep on the fastest and most expensive storage arrays. They operate 24/7 and are given priority when it comes to administration, maintenance and IT budgets.
It stands to reason, then, that infrequently or occasionally accessed data ought to reside elsewhere. You don’t want to offload it to tape because you need ready access to it (VTLs are help in terms of speeding up backup and recovery, but it’s beyond the scope of this article), but neither do you want it consuming energy during the days, weeks, or even months that it’s not in use.
MAID stands for Massive Array of Idle Disks. If you’re unfamiliar with technology, the Wikipedia entry does a good job of illustrating the point by describing it as “not unlike a very large JBOD but with power management.”
Essentially, specialized arrays, management software and some logic combine to store data on inexpensive SATA hard drives that spend most of their time powered down, or idle. When data is requested, the respective drive is spun up and the data is then retrieved.
Of course, this process introduces a bit of a delay, but the cost savings in terms of saved energy makes it worth waiting a few (sometimes several) extra seconds until the information you request arrives at your workstation. This minor hit to productivity can be offset by automating scheduled or routine tasks.
Typically, the software controlling the MAID will feature automatic diagnostic routines that spin up the drives on occasion to check on the integrity of the disks and prevent data rot.
And just like the word this acronym spells out, a MAID can help you keep your storage network neat, clean and efficient by providing a pool of storage for data that you don’t want cluttering your high performance storage systems nor buried in archives. This, in turn, creates an energy efficient tier within your data hierarchy plan — a concept that’s becoming increasingly vital as tiered storage schemes and data center greening initiatives meet.
Wondering where to procure this technology? Below I’ve compiled a short list of MAID storage vendors. If I missed some (very likely), send a shout in the comments!