CrashPlan (formerly CrashPlan PROe) provides “continuous backup” that’s different from other, more traditional backup applications. Rather than kick off a resource-intensive backup session once or twice a day, it's much more lightweight and unobtrusive.
CrashPlan uses your computer’s built-in notification system to learn about changes to your data. It listens to your operating system to learn when files have been added, removed or modified. It queues up the eligible files, then compresses and encrypts the data prior to sending them over the network. This happens every fifteen minutes by default.
Just to make sure no files were missed, there is a once-a-day disk scan to account for any changes that might have been overlooked. This usually happens around noon each day. If your computer was turned off, that scan will take place later in the day.
Initial backup, subsequent protection
After the initial backup is complete, only the changed bytes of any given file is sent subsequently. Additionally, on a per-device basis, CrashPlan provides deduplication to make backups more efficient.
To restore data, use the secure web interface to recover a few files, or use the desktop software for larger tasks. See the CrashPlan documentation to learn about restoring files.
The integrity of your backups are verified regularly by the software. Any corruption in the backup archive will be identified and the original files are backed up again to ensure protection.
By default, CrashPlan uses minimal CPU and network resources while your computer is being used. Users can throttle the network usage to prevent disruptions on home networks, too.