[BBLISA] ZFS Anyone?

[Theo Van Dinter]

On Sat, Apr 4, 2009 at 12:47 AM, Edward Ned Harvey
<bblisa3 at nedharvey.com> wrote:
> I'm not sure what you mean by replication.  Mirroring?  Send?  Based on your
> wording, I think you're talking about something like this, no?
>        zfs send | ssh somehost "zfs receive"

Sorry, yes, I was talking about machine-machine replication.

> Why would you have to do the decompress/recompress thing?  What about ...
>        zfs send | gzip -c --fast | ssh somehost "gunzip -c | zfs receive"

Assuming a compressed volume on the source machine, when you do a "zfs
send", it reads the blocks off the disk and uncompresses them and
generates a stream.  You then would want to compress it to send it
over the network so the stream is smaller.  On the destination, you
need to uncompress the stream for processing.  Then, assuming an
identically configured volume, when the data is written to disk it
gets compressed again.

>> I very much look forward to linux+zfs.
> I'm not sure that zfs will ever make it to linux, for the aforementioned
> legal reasons.

If IBM buys Sun, though, I'm sure they can change the license to be
whatever they want.  :)

> But I hear that BTRFS is going to be the linux equivalent.
> Don't really know anyting about it myself.  Just what I'm told.

Yeah, I haven't played with it yet either.  A quick poke around seems
to show a few things that turn me off about it, like having to do COW
for snapshots (boo!), but I've been ignoring it until it's actually
out of "development only" mode.