Statistical modeling and analysis of hard disk drives (HDDs) failure

The meantime to failure (MTTF) specified in HDDs data sheets, suggests a constant failure rate with the failure probability density following an exponential distribution. However, actual field data of HDD replacement indicated the failure rate is not a constant with age. This could be due to the complexity nature of the HDDs' structure and underlying failure mode. Based on the gathered user field data of HDD failure, this article provides an evaluation of Weibull modeling, with exponential modeling as a special case in reliability modeling of HDDs. It concludes a two stage sectional Weibull modeling performs adequately in modeling HDDs failure through 5 years lifetime.