Performance analysis of two frozen image based backup/restore methods

Backup and restore are critical tasks performed on every system that holds important data. This paper evaluates the performance of two innovative backup methods based on frozen image technologies. VERITAS netbackup instant recovery option utilizes frozen images created from file system or volume manager utilities and manages these frozen images as backups. Because creating frozen images involve no actual copying of data, such backups are significantly faster. In addition, the frozen images reside on online storages, making restore from them much more efficient as well. In this paper, we conducted backups and restores in a database environment to demonstrate the advantages of using the frozen image based backup/restore with the VERITAS file system's storage checkpoint and VERITAS volume manager's volume snapshot. With both methods, taking a full backup of a 26 gigabytes database took less than 4% of the time compared to traditional tape-based backup. The amount of time to restore different database objects from frozen images ranges from 3 to 47% of the time restoring from tapes. While both backup and restore from frozen images are much more efficient than traditional backup methods, they are meant to complement, not to replace the traditional backups. This is because frozen images share common resources with the system they are protecting and are subjected to the same risks that might damage the data. The traditional backup method offers protection against a wider array of risks that can cause data loss and should be kept in as part of an overall data protection strategy