[BBLISA] RE: storevault / netapp

[Peter Galvin]

Rob, I should have been more clear. You could expand a RAIDZ/Z2 set with a
single disk but you don't want to.

There are certainly ways to add storage to ZFS pools. But you cannot add a
single disk to a RAIDZ or RAIDZ2 pool to expand its capacity, reliably. If
you just add a single disk to a RAIDZ set as you show with your "add"
command, you would end up with a RAIDZ set plus a concatenated single disk
(i.e. That added disk is not RAID protected). Instead you could add for
example another RAIDZ2 set to an existing RAIDZ2 set.  See this Sun manual
for example:

http://docs.sun.com/app/docs/doc/817-2271/6mhupg6iu?l=en&a=view&q=zfs+add

And this discussion:
http://www.opensolaris.org/jive/thread.jspa?messageID=106364&#106364

--Peter

Blog: http://pbgalvin.wordpress.com

On 2/27/08 1:44 PM, "Rob Cambra" <robc at solarflares.net> wrote:

> On Wed, 27 Feb 2008, Peter Galvin wrote:
> 
>> At the moment ZFS cannot expand a storage pool by single disk increments.
>> You could for example expand a RAIDZ pool by concatenating another RAIDZ set
>> to it, but not by adding a single disk.
> 
> Sure you can, "zpool add $poolname $device"
>