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I'm currently working on a disaster recovery plan using fsarchiver. I have very limited experience with it so far, but it had the features and social proof I was looking for.
I have so far used it to create offline filesystem backups of two volumes, one was LUKS encrypted (has to be manually "opened" with cryptsetup).
It can backup live filesystems which was important to me.
It's early days for my experience with this, but I'm sure others have used it and might chime in.
Rsync is great but if you want snapshots and file history rsnapshot works pretty well. It's based on rsync but for every sync it creates shortcuts for existing files and only copies changes and new files. It saves space and remains transparent for the user. FreeFileSync is also amazing