C-Command Software Forum

Encrypted library backup diffs

I was interested in EagleFiler to store / organize my financial documents. Because of the sensitive nature of these docs, I’d like to store them in an encrypted library. I regularly back these up to offsite storage using rsync and/or duplicity.

In a normal file structure, if I add a 1MB file in an 100MB library, rsync / duplicity will only sync the diffs (ie. 1MB). However, if I’m using an encrypted library within EagleFiler, will rsync still be able to transfer just the diffs in that case? (I ask because it looks like EagleFiler uses encrypted disk images to store the encrypted library, which show up as a single file to OS X) I know duplicity will do block level diffs, but I’m not exactly sure if the structure will change completely when adding files to an encrypted disk image.


When you modify an encrypted library, only parts of the sparseimage file are changed. So backups with rsync should be quick. (I’m not familiar with duplicity or how it works.) Be sure that you unmount the sparseimage before starting your backup.