Take Control of Mac OS X Backups, Fourth Edition

Keeping Multiple Backups

A sound backup strategy always includes backups of your backups! Picture this: You've diligently backed up your computer's internal hard disk to an external drive. One day, lightning strikes and both drives are damaged. So much for your backup. Even under ordinary circumstances, backup media can fail for all the same reasons your hard drive can fail. So having just one backup, in my opinion, is never enough. You should alternate between two or more sets of backup media for greater safety. If you've set up your backups to run on a schedule, this might mean using set A (a hard drive or a stack of CDs) every day for a week, then switching to set B (a different drive or stack of CDs) for each day of the following week, then ...