A systems administrator is reviewing the company's disaster recovery plan and discovers that while backups are performed nightly, their validity is only checked by confirming a successful job status in the backup software log. To improve the plan and specifically address the physical and logical health of the backup media, which of the following validation techniques should be implemented?
Conducting a full restore to an isolated test environment.
Performing routine maintenance on the tape drive, including cleaning the heads.
Periodically performing a checksum verification on the backup files.
Implementing a Grandfather-Father-Son (GFS) media rotation scheme.
The correct answer is to periodically perform a checksum verification on the backup files. A checksum or hash (such as MD5 or SHA-256) is a unique signature calculated from the data in a file. By calculating the checksum when the backup is created and then recalculating it later, an administrator can verify that the data has not been corrupted or altered on the media, thus ensuring media integrity.
A full restore to a test environment validates the entire recovery process, not just the media integrity. While a successful restore implies the media is good, the primary goal of a checksum is to specifically and efficiently test the data on the media itself. The Grandfather-Father-Son (GFS) scheme is a media rotation and retention strategy, not a data validation technique. Performing routine maintenance on a tape drive is a hardware maintenance task to prevent future errors, not a method for validating the data on existing backups.