I’m currently using Carbonite to backup my files to the cloud and I have noticed that if you move a file from one place to another without making any changes to it the file has to be backed-up again. I’ve also emailed support at JustCloud to ask if they also do this and apparently they do.

Does anyone know of any backup services that don’t re-upload unmodified but moved files? I recently had a fairly significant move around of my files and Carbonite pretty much had to start again, backing-up some 70GB of data, which I felt was rather ridiculous.

closed as off topic by Eight Days of Malaise, ChrisF Oct 15 '12 at 12:26

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Since you're already on OS X, you've got two solutions, both of which fit your requirements.

If you're okay using a "big-name" data provider, I'd strongly suggest using Backblaze, which both de-duplicates redundant data (i.e., any given file will only be uploaded once, no matter how many times you copy or move it), and uses rolling hashes so that most small changes to larger files will not require uploading the entire file again. You can read more in Backblaze's FAQ.

Alternatively, if you want full control over your backups, Arq provides identical features, but uploads to your own Amazon S3 account so that you can more directly manage your security.

  • I did BackBlaze’s trial but there was something about it that was a dealbreaker for me. Unfortunately this was some time ago so I can’t remember what. I think it might have been to do with it only uploading certain types of files but I’m not sure. – Ollie Saunders Oct 6 '12 at 21:59
  • Backblaze defaults to not backing up a lot of larger file types, and has a hard-cap around a gig or so, if I remember correctly. Arq, however--my other suggestion--has neither of these drawbacks. I'd take a look at it. – Benjamin Pollack Oct 8 '12 at 13:10

Although it is not aimed for Cloud Backup, git has that functionality.

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