[lsc]

>Linux will soon have btrfs, which is as good as (if not better than) ZFS.

btrfs does not even try to solve the problem I want zfs for; snapshots over the network.

You see, when you deal with a large amount of storage (especially if you deal with that storage as block devices that run arbitrary filesystems, and not just files on a filesystem) the bottleneck for backups becomes disk bandwidth, not network bandwidth, so things like rsync don't help much.

ZFS snapshots over the network? those help rather a lot. Unlike rsync and stuff, it saves me disk bandwidth, not just network bandwidth. Unlike inotify-based systems, I don't need to have knowledge of the filesystems I'm replicating.

(I know I harp on this a lot... I just want to point out that btrfs, no matter how good it is for the problems it attempts to solve, isn't even trying to solve the problem I need ZFS for.)

[rogerbinns]

> btrfs does not even try to solve the problem I want zfs for; snapshots over the network.

This a recent Ubuntu system (ie not using development trees etc)

    $ btrfs send --help
    usage: btrfs send <command> <args>

        btrfs send [-v] [-i <subvol>] [-p <parent>] <subvol>
            Send the subvolume to stdout.

    $ btrfs receive --help
    usage: btrfs receive <command> <args>

        btrfs receive [-v] [-i <infile>] <mount>
            Receive subvolumes from stdin.

[lsc]

Ooh. thanks. this post is probably the most useful bit of information I've read this month. Hm. I will have to research more, but this might... change things significantly. I mean, it's still a newish feature, not something you want for backups, but between that an bcache, Linux looks like it might deserve another look, storage-wise.

[gonzo]

At <company I work for, which owns pfSense> we use ZFS for exactly this. Functional, always 'on' backups to the hosting center next door (we have some nice single-mode fiber running to our cabinet there.)