When comparing duplicity vs CrashPlan, the Slant community recommends duplicity for most people. In the question“What are the best backup programs for Linux?” duplicity is ranked 2nd while CrashPlan is ranked 14th. The most important reason people chose duplicity is:
Data is encrypted locally before being sent, and kept encrypted by a key that is never stored on the remote machine. So you might even store your data on a public space, people would still need your key or brute force it.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Encrypted locally before sending (using GnuPG)
Data is encrypted locally before being sent, and kept encrypted by a key that is never stored on the remote machine. So you might even store your data on a public space, people would still need your key or brute force it.
Pro Bandwidth and space efficient
Duplicity uses the rsync algorithm so only the changed parts of files are sent to the archive when doing an incremental backup. For instance, if a long log file increases by just a few lines of text, a small diff will be sent to and saved in the archive. Other backup programs may save a complete copy of the file.
Pro Versioning and incremental backup
You can retrieve older versions or files you recently deleted locally even after having updated your backup.
Pro Free and open-source
Licensed under GNU GPL v2.
Pro Works with scp/ssh, ftp, rsync, Amazon S3...
Duplicity does not make many demands on its archive server. As long as files can be saved to, read from, listed, and deleted from a location, that location can be used as a duplicity backend. Besides increasing choice for the user, it can make a server more secure, as clients only require minimal access.
Pro Has a Dockerized image
Docker allows to run programs on any Linux without having to really install them, and allows to manage versions so it runs exactly the same on different machines.
Pro Unintrusive
You set it up once and from then it runs in the background whenever you are not using your computers (or at specified times).
Pro Supports multiple backup destinations
You can set up different files/folders to back up to specific places.
Pro Differential and incremental file backup
CrashPlan updates only that part of the file that has changed, saving bandwidth and time.
Pro Unlimited online storage
The $5/mo individual plan and the $12.50/mo family plan gets you unlimited cloud storage.
Pro Allows custom encryption keys
Custom 448 bit user-provided encryption key can be used to encrypt the backed up data in the cloud.
Pro Users can order a physical copy of their data
They will send you an external hard drive to your house.
Pro Unlimited revision history
CrashPlan saves all previous versions of a file.
Cons
Con You have to invest a few minutes in setup time
Con Buggy
Con Home edition discontinued
CrashPlan's home edition will be shut down on October 23, 2018. They are no longer accepting new signups or subscription renewals.
Con Popular features (local backup and trusted offsite backup) no longer available
Con Heavy client
The BackupClient is based on Java and therefore a lot more memory-intensive than most other backup solutions