On 14 Sep 2017, Wols Lists uttered the following: > On 14/09/17 12:08, Nix wrote: >>> The rule is simple - don't abuse your tools, and btrfs - USED WITHIN ITS >>> > LIMITATIONS - is a powerful and reliable file system. > >> Yeah, but... if you avoid the advanced features, why use btrfs? In >> particular, why use it *for a backup medium* (where such features are >> distinctly less useful than on a non-backup medium)? > > Because, if you use snapshots and an "in-place rsync" (which overwrites > the part of files which have changed, rather than replacing the file by > default), then each snapshot is a full backup, but only uses the space > of an incremental. Ah, so it's like bup only immediately accessible without Python and FUSE installed, and probably less reliable (but hopefully this will change.) Except it doesn't do full deduplication (if you change a file, it gets backed up, even if you change it to the same contents as it had before: yeah, perhaps this is a tad contrived). > The OP was building a backup server, so all their live data is > elsewhere, and provided you look after your backups, this will give you > a very cheap and effective backup system. Backups based on not-yet-reliable filesystems are, uh, less effective. (I've lost backups to bad filesystems before due to turning on options that weren't ready for prime time :( ) -- NULL && (void) -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
