In doing some research recently on the problems associated with recovering data from old tapes, I found out that a similar set of problems exist when trying to recover data stored on old disks. This problem becomes especially pronounced if a company unplugs an old disk drive and puts it on the shelf or keeps it in production too long.
The problem that companies are more likely to encounter when storing a disk drive on the shelf is not necessarily data degradation on the disk drive platter but mechanical failures of the parts within the disk drive itself. Greg Schulz, the lead analyst with Minneapolis-based StorageIO, finds that the lubricants of the mechanical parts within the disk drive can settle. This can cause the disk drive to malfunction when the company attempts power it up again for the first time in a long time.
Jim Reinert, VP of disaster recovery for Kroll Ontrack, a worldwide provider of data recovery services, says that the largest problem Kroll encounters with trying to recover data from old disk drives is repairing and replacing defective mechanical parts inside the disk drive. Motors failing and electronic circuit boards going bad are just some of the components Kroll has had to repair before it can recover the data from the drive. This situation requires Kroll to find an exact match for the defective part, usually on the used market.
Of course, mechanical problems can also occur while the computer system is still in use. Reinert finds that some of the toughest data to recover is found on older, proprietary computer systems that are in use but break. Typically found in manufacturing and production environments, these are older computer systems that control a piece of equipment that everyone uses but no one manages. As a result, the data is not backed up nor does anyone know who created the application or how it runs.
So, what’s the best way to protect data on old disk drives? The best and simplest way is to avoid keeping data on old disk drives and migrate data to newer disk drives. Kroll Ontrack classifies disk drives over five years in age as “old” since by this time disk drive warranties have usually expired and parts for the disk drive are out of production.
Schulz is a little less dogmatic about the five year cut-off. He finds that disk drives that are up to seven to eight years in age are probably OK depending on what condition in which they were stored or how they are used in production. He suggests spinning them up on a regular basis (once every 3 to 6 months), though he agrees that as disk drives age, administrators should migrate the data to newer drives.
If a disk drive has already failed or you come across one of indeterminate age or condition and you don’t know what data is on it or its value to your business, your best bet is probably to send it to a data recovery specialist and keep your fingers crossed.