Which do you prefer and why for HDD or SDD hard disks ? And how is Ext4 with power failures nowadays ? iirc a few years ago there were issues with Ext3 (Yes, Ext3) and I remember a no barrier option was needed ? Is Ext4 much better ? And what FS do you prefer on usb storage ?
In BTRFS if you copy a File to another folder, only the reference is created. The physically information, what IS the file, is still the same. If you use [code]cp --reflink=always[/code] for sure.
So if you make a Snapshot with BTRFS, it’s almost like a hardlink. The file disappears, when the last reference gets deleted. But al reference-files break, if the physically location on the HD breaks.
So… making a snapshot in btrfs is not a backup for me. It is a good way for a fast rollback. It is a good way for deduplication. It is a good way for daily work. But a real backup for me is a physically separated store for the information.
Make snapshots on a computer for fast rollback, or after system upgrade - even here for fast rollback. Or if I’m working on my photos, i do automatically every 10 minutes a snapshot. So a wrong command does only destroy the work of maximum 10 minutes… never the whole work.
But backup… i make differential snapshots and send them with btrfs send/receive to another drive, so the snapshot is pyhsically duplicated on a separate store. One HD can break… i have a backup.
Do you understand, what i mean?