On 14 Sep 2017, Roman Mamedov said: > On Thu, 14 Sep 2017 16:02:31 +0100 > Nix <nix@xxxxxxxxxxxxx> wrote: > >> I would never consider snapshots on the same filesystem to be a backup >> of anything, except possibly as a defence against 'oh whoops I rm'ed the >> wrong tree'. > > No one proposed that. Oh I thought that was what people were proposing as the compelling btrfs advantage. > The scenario is that the backup server would have its > rsync destination dir (from multiple other systems) periodically snapshotted, > providing a historic view of what it contained 1-2-3 months ago. Just like > "bup" does in userspace, I guess? -- or like rdiff-backup did, which I used > before. But now we have that directly in filesystem, no need to cling to > userspace crutches anymore. I'm fairly sure that can't deduplicate anywhere near as effectively. No dedup within files; no dedup across trees (very important if you have duplicated data on multipl systems you are backing up); no dedup anywhere except in immediate history. That's all rdiff-backup could do, but the state of the art is better now. -- 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
