Rebuilding a failed disk in a disk array

Provided are a method for operating a disk array, a disk array, and a rebuilding process. The disk array comprises a plurality of data disks and a parity disk. A failed data disk in the disk array is detected and the failed data disk is isolated from the disk array. A rebuild is initiated of the data in the failed data disk to a spare data disk from data in surviving data disks comprising the at least one of the data disks that did not fail and the parity disk in the disk array. An error is detected in one of the surviving data disks. Data is read from the failed data disk. The rebuild of the failed data disk is completed using the surviving data disks, the parity disk, and the data read from the failed data disk.