Ken D'Ambrosio <k...@jots.org> writes:
> On 2022-02-24 11:31, Ian Kelling wrote: >> Chuck McAndrew <chuck.mcand...@adhocteam.us> writes: >> >>> I would add one feature about ZFS that is super useful and that is >>> the ability to replicate datasets to a remote server. I don't know if >>> btrfs has a >>> similar feature, but the ability to have a backup server offsite and >>> just setup a cron job to replicate it was awesome for DR. It makes >>> backing up >>> your snapshots very very easy. >>> >> Yes, btrfs has this. I use it mostly through this tool: >> https://github.com/digint/btrbk . I recommend it. > > I use the btrfs-send (which, of course, is modeled after > zfs-send)... except, I kinda don't. And this isn't a dig at btrfs (or > ZFS), but just paranoia: I'm afraid that, if there were corruption on > the source FS, using a FS-specific/replicating tool to do the data > transfer might bring over whatever corruption was on the source in the > first place. > So what I do: > > * Create a copy on the destination host. > * Snapshot it. > * Mount the snapshot as my rsync backup destination. > * And make a snapshot of _that_. > > That way, I have two essentially identical CoW hierarchies, but that > have "left" the source FS, and gone to the destination one. Not as > efficient as sending CoW deltas, but it gives me a little more peace of > mind. Yes, my scenario seems awfully unlikely, buuuuuuuuuut... I'm confused by those bullets, I understand the general idea though. I think that it is a valid concern. I don't worry about btrfs send deleting data, so much as a filesystem having some metadata error propagated that you need a btrfs expert to help you correct before you can mount it read-write. The same concern applies to ZFS. It reminds me of the 2 media types recommendation of 3-2-1 backup strategy https://www.backblaze.com/blog/the-3-2-1-backup-strategy/ An rsync-like solution is simpler and more flexible in a bunch of ways, and even more performant in some ways. For FSF servers, we use a restic wrapper we wrote, https://github.com/leaf-node/kaya. btrfs-send and wrappers like btrbk are not my first recommendation for backups unless someone really wants or needs their specific benefits. -- Ian Kelling | Senior Systems Administrator, Free Software Foundation GPG Key: B125 F60B 7B28 7FF6 A2B7 DF8F 170A F0E2 9542 95DF https://fsf.org | https://gnu.org _______________________________________________ gnhlug-discuss mailing list gnhlug-discuss@mail.gnhlug.org http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/
