3 ms·

Added, do you have some more info on that one, drawbacks, performance?

• jpgvm 12y ago
  De-dupe, will only transfer blocks changed since last snapshot. Performance, it's super damn fast. Because the ZFS snapshot itself is just a stream you can also compress it on the wire. Flexibility. You don't need to send the snapshot to another ZFS server. You could just take the ZFS snapshot streams and store them on say S3 compressed and re-assemble them. This would take custom tooling but it's definitely possible. You can restore super quickly to an older version if you haven't deleted the local snapshots. Similar to above but if you don't want to restore (as in make said snapshot the current active dataset) you can create a writable clone of one of the snapshots to play with it before committing to a restore or just to "go back in time" and play with something. As a bonus you also now have your data on ZFS which has tons of great benefits apart from the point in time snapshots.
• mhw 12y ago
  I'm using zfs-auto-snapshot[1] and zfs send/recv to backup my work desktop machine to a remote server. The naive approach of just doing 'zfs send -R -I snap1 snap2 | ssh remote zfs recv -dF pool'[2] has a number of drawbacks: * Assumes remote is available 100% of the time. Recovery from downtime at the remote probably requires some manual intervention to get things back in sync. * If the remote is in a different physical location with limited bandwidth between the hosts, compressing the stream on the fly isn't going to be particularly efficient with bandwidth. I've built some scripts to help[3], dumping the necessary incremental streams into a local directory and then compressing them with lrzip[4]. This decouples the host and remote systems and the zfs streams compress really well: a 33Mb incremental stream I have here compresses to 4.4Mb with lrzip. Once you have a directory of compressed streams you can push them wherever you want (a remote server where you convert them back into zfs snapshots, giving you a live filesystem; S3 buckets etc.) You also are able to restore using standard operating system tools. I'd assume btrfs is comparable, but haven't tried it myself. [1]: https://github.com/zfsonlinux/zfs-auto-snapshot https://github.com/zfsonlinux/zfs-auto-snapshot [2]: see https://github.com/adaugherity/zfs-backup https://github.com/adaugherity/zfs-backup for example [3]: currently in my local fork of zfstools at https://github.com/mhw/zfstools/blob/master/bin/zfs-save-snapshots https://github.com/mhw/zfstools/blob/master/bin/zfs-save-sna... [4]: http://ck.kolivas.org/apps/lrzip/README http://ck.kolivas.org/apps/lrzip/README