If you’re already backing up your Mac—perhaps by following the simple steps in “Backup Basics”—pat yourself on the back. Having any sort of backup is much better than having none, and your probability of recovering from data loss is dramatically increased. But for many people, a barebones backup strategy won’t cut it. If your livelihood depends on your data being available at all times, if you’re in the middle of a time-sensitive project, or if you’re just paranoid and want to make sure nothing has fallen through the cracks, you may want more of a guarantee.

How can you turn so-so backups into fantastic, bulletproof backups? Although everyone’s situation is a bit different, I have several recommendations that should vastly improve the quality and reliability of any backup plan.

Save old versions of files

One type of backup everyone should have is a versioned backup, which means your backup software continues to store older versions of your files when you change or delete them. OS X’s Time Machine does this automatically, as do Dropbox, CrashPlan, and the majority of modern backup programs. (OS X 10.7 Lion and later can automatically store multiple versions of your files, but this capability works only in apps that have been written to support it.)

Which software you use and the exact implementation details are less important than the outcome—if you (or a family member, coworker, or even a pet) inadvertently change or delete information in a crucial file, you want to be able to go back to an earlier state of that file before the mistake happened, even if that was weeks ago.

Some backup software saves new versions on a fixed schedule (for example, Time Machine runs once per hour), while other software lets you choose the backup frequency or watches files for changes and then backs them up immediately or after a user-defined interval (CrashPlan falls into this latter category). Given the choice, opt for more-frequent versioned backups.

Versioning is important, but by itself, it’s not enough. Your backup strategy also needs a few other key components.

Source: www.macworld.com