Consumer vs Enterprise Drives Does It Matter?

Yes it does, but the reasons why might surprise you.

Why Type of Drive Matters
Working in the data storage industry and working with organizations that want to save money and cut costs any way they can we hear a lot of questions and opinions regarding the “real” difference between SATA vs SAS, enterprise drives vs consumer drives, OEM server drives vs New Egg.

And lately it has come up more often than ever before. I think it is related to the surge in SSD’s within the data center and the drastic difference in price between SAS and SATA SSD’s as well as consumer vs enterprise class SSD’s.

The reason that consumer vs enterprise drives matters so much is that the drives are designed and programmed for the corresponding situation. In a server or storage array the drive is programmed to behave one way. A consumer grade drive is designed with the assumption of working in a desktop or laptop.

Consumer drives are designed for situations assuming there is no raid card.  Consumer drives handle their own error correction and block re-allocation just like the enterprise drive.  The big difference is that the consumer drive does not issue error messages or respond to the host bus adapter’s commands during this period. Consumer hard drives are designed with the assumption they should do everything possible to complete error correction because there is no RAID controller to assist with error correction and recovery. Meanwhile, RAID cards are typically programmed to wait 8 seconds for a drive to respond, and if the drive does not respond, take action. It is not uncommon for a drive under a continuous I/O load performing its own error recovery to easily exceed 8 seconds. This becomes a major problem when error correction takes longer than 8 seconds, the RAID controller assumes the non-responding disk has failed and then the RAID controller drops the hard drive from the RAID volume.

Using an enterprise drive in the RAID environment would allow the drive to respond and report appropriately to the RAID controller about its behavior and actions to potentially defer or prevent the RAID controller from removing the disk from the RAID volume.  This proper coordination can save a lot of time and avoid an array having to go through a long and painful rebuild process and the mistake of returning/replacing a perfectly healthy drive.

Using a drive for something other than the situation it is designed for can lead to problems that are unpredictable and difficult to detect.  When you consider the cost of human resources to track down these issues or interruption in operations it can easily surpass the price difference between the consumer and enterprise class drives.