- Can be resumed
- Progress indicator (kindof)
- Runs across ANY filesystem
- Easy to debug
- Tried & tested !
- rsync-ing a running system is like booting a system after a power cut
- Rsyncing to a crappy filesystem might lose metadata
- You can't realistically roll back without fs dependant hacks like hardlinks
A new entrant! Is it actually ... BETTER than rsync?
- A snapshot (to be backed up) can be made instantly on boot or on poweroff, when the files aren't open
- Works nicely with systemd-nspawn so you can safely test mirrors of your filesystem
- Easier to roll back
- Can store more efficiently
- You need to setup the snapshotting regime
- Complex, probably buggy and fallible (potentially dangerous)
- btrfs send cannot be resumed, so if you sending a backup somewhere remote and it's interrupted... start again!