Patent ID: 8015441

Claim:
A method of backing up source data from a source storage volume of a source computer to backup media, comprising: reading at least a portion of the source data from the source storage volume; generating by the source computer a hash of the source data as the source data is read from the source volume; transmitting the source data and hash to said backup media; writing the source data to said backup media as backup data; writing the hash to the backup media; associating the hash on the backup media with the backup data corresponding to the source data from which the hash was generated; reading the backup data and the hash from the backup media by a backup server that controls the back up media; generating by the backup server another hash from the backup data read from the backup media; comparing by the backup server the hash read from the backup media with the other hash generated by the backup server to verify the integrity of the backup data; and upon said compared hashes not matching, marking the backup data as miscomparing, rereading by a source computer the source data corresponding to the miscompared backup data media from the associated source volume, and rewriting the source data to the backup media with a new hash generated from the reread source data by the source computer.