Patent attributes
Disclosed are solutions for resolving a redundant array of independent disks (RAID) write hole, or a parity-based fault scenario that occurs when a power failure and a drive failure occur at or close to the same time. Drive array controller logic assigns a sequence number to write operations received from a computing system and converts respective write operations, including corresponding sequence numbers, to a multiple-drive write to a series of RAID drives. A microcontroller at each drive writes, to a history log (HLOG) on the drive, a logical-to-physical address mapping of a prior sector of the drive that was written along with a corresponding sequence number. Upon receipt of a new write to the mapped logical address, the microcontroller removes the HLOG entry for the logical address, and writes a new entry to the HLOG with a new physical address mapping to the logical address with a new sequence number.
