US Patent 8010835 Storage device realignment

Realigning storage devices arranged as storage arrays when one of the storage arrays enters a critical state after failure of a storage device is disclosed. The method is particularly useful for RAID groups of storage devices. The method may be used with hard disk drives, solid-state drives, and other storage devices arranged as groups. The method includes identifying when a storage array of a plurality of storage arrays is in a critical condition. A critical condition storage array and a healthy storage array are identified. Both the critical condition storage array and the healthy storage array are rebuilt. The rebuilding includes configuring the critical condition storage array to include a storage device from the healthy storage array and configuring the healthy storage array to function with one less storage device. The method may be implemented in hardware, firmware, software, or a combination thereof.