In our data sets, the replacement rates of SATA disks are not worse than the replacement rates of SCSI or FC disks. This may indicate that disk-independent factors, such as operating conditions, usage and environmental factors affect replacement rates more than component specific factors.
quote: I don't think they are so much exaggerated as the term MTBF is just misunderstood.
quote: The Manufacturer runs 1000 drives on a test bed for 1000 hours . If one fails it is 1,000,000 hours MTBF (1000x1000). In reality its a bit more complex, but that is the jist of it. MTBF is not a relative rating on how long your hard drive should last
quote: ...indicating that there is a need to manufacturers to reevaluate the way a MTBF rating is generated.
quote: The number one cause of drive failures according to the study was simply age. The longer the drive has been in operation, the more likely it will fail. According to the study, drives tended to start showing signs of failure after roughly five to seven years of service, after which there was a significant increase in average failure rates (AFR). The failure rates of drives that were in their first year of service or shorter was just as high as those after the seven year mark.
quote: Observation 5: Contrary to common and proposed models, hard drive replacement rates do not enter steady state after the first year of operation. Instead replacement rates seem to steadily increase over time.Observation 6: Early onset of wear-out seems to have a much stronger impact on lifecycle replacement rates than infant mortality, as experienced by end customers, even when considering only the first three or five years of a system's lifetime. We therefore recommend that wear-out be incorporated into new standards for disk drive reliability. The new standard suggested by IDEMA does not take wear-out into account