Data availability is a term used by computer storage manufacturers and storage service providers (SSPs) to describe products and services that ensure that data continues to be available at a required level of performance in situations ranging from normal through "disastrous." Anytime a server loses power, for example, it has to reboot, recover data and repair corrupted data. The time it takes to recover, known as the mean time to recover (MTR), could be minutes, hours or days.