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I just had a short look. Currently snapper luckily fulfills my needs. Currently I have RAID1 set up via btrfs (not a good backup, or depending of the definition of "backup" not a backup at all - I still think one cannot deny that it reduces the risk of data loss). On top of that I have important data on an external drive that I plan to sync to manually regularly (this might be where btrbk might come in useful, as it is probably able to retain all the snapshots (history) on the backup drive instead of just overwriting the data when syncing. Currently I don't have the time to thoroughly look into it, though). Also I plan to use rclone to sync with a cloud service. I also think that depending of the definition of "backup", snapshots can be seen as one. But again of course not a safe one. It all comes down to lowering the risk of data loss in the end. And finding a solution that is an acceptable balance between cost (or effort) and risk. Von: Graham Cobb Gesendet: Dienstag, 22. Dezember 2020 00:33 An: Claudius Ellsel ; Remi Gauvin Cc: linux-btrfs Betreff: Re: AW: WG: How to properly setup for snapshots   On 21/12/2020 20:45, Claudius Ellsel wrote: > I had a closer look at snapper now and have installed and set it up. This seems to be really the easiest way for me, I guess. My main confusion was probably that I was unsure whether I had to create a subvolume prior to this or not, which got sorted out now. The situation is apparently still not ideal, as to my current understanding it would have been preferable to set up a subvolume first at root level directly after creating the files system. However, as this is only the data drive in the machine (OS runs on an ext4 SSD) it is at least not planned to simply swap the entire volume to a snapshot but rather to restore snapshots at file / folder level, where snapper can also be used for. > > One can possibly also safely achieve the same with only using btrfs commandline tools (I made the mistake of not thinking about read only snapshots when I wrote about my fear to delete / modify mounted snapshots). Still I have a better feeling when using snapper, as I hope it is less easy to screw things up with it :) I have never used snapper but I know it is a popular tool. But there are many other tools - with their own advantages, disadvantages and ways of working. You may want to experiment with several of them. Personally I use btrbk for automation of snapshots. Just remember that btrfs snapshots are not a backup tool. At best, they are a convenience tool, for quickly restoring deleted or modified files (or full subvolumes) to an earlier (snapshotted) state without having to access your backups. But they are completely useless if a hardware or software problem (kernel bug, disk problem, system memory error, faulty cable, etc) corrupts the filesystem. You don't have a backup solution unless you are copying the files to another physical disk, preferably on a different system. btrbk can help with that as well (but it is just automating btrfs send and btrfs receive underneath).