EXPANSION OF THE NUMBER OF DRIVES IN A RAID SET WHILE MAINTAINING INTEGRITY OF MIGRATED DATA

摘要

A method and apparatus for dynamically expanding an N drive RAID set to an M drive RAID set while maintaining data integrity, where the M drive RAID set includes one or more new drives. The method comprises the steps of identifying a destructive zone in the N drive RAID set including destructive zone data (400). Thereafter the destructive zone data is mirrored in the M drive RAID set by copying it to a free location in the N drive RAID set (408) and to a location in a new drive in the M drive RAID set (410). Finally, the N drive RAID set is expanded to an M drive RAID set (414). Data integrity is assured in the N drive RAID set during migration by maintaining mirrored destructive zone data until the expansion step has completed migration of the destructive zone of the N drive RAID set (416).