 "RAID 10" is distinct from "RAID 0+1," which consists of a top-level RAID 1 mirror composed of high-performance RAID 0 stripes directly across the physical hard disks.A single-drive failure in a RAID 10 configuration results in one of the lower-level mirrors entering degraded mode, but the top-level stripe performing normally (except for the performance hit).A single-drive failure in a RAID 0+1 configuration results in one of the lower-level stripes "completely failing," and the top-level mirror entering degraded mode.