Note, however, that most cloud backup services automatically sync and update data. If your local PC is compromised, you'll want to disable the service to prevent the compromised data from overwriting your good backup data.
Back up multiple versions
The most effective way to safeguard your backup is maintain more than one copy of your data.
There are two ways to do this. First, most security experts recommend backing up your important data to more than one location. For example, back up to an external USB drive that you disconnect when it's not in use, and also use a cloud backup service. That way if infection or physical disaster compromises either backup, you'll still have a good copy of the data.
The second way is to maintain version histories of your files: Save multiple backups from different points in time, and choose a cloud backup service that stores more than just the most recent backup, so you can restore data from a time before the compromise occurred.
"I go a step further and also create several generations of local and off-site image backups of my computer, so I can quickly restore one of them if my system is lost, compromised, or otherwise unusable," Tripwire's Melancon says.
Your backup drive needs a backup plan. Without one, you're not much better off than if you'd never backed up in the first place. Follow one of the methods laid out here to ensure that your backup will be there—in readable form—when you need it most.
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