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Date: Wed, 26 Jan 2011 09:42:42 +0100
From: "O. Hartmann" <ohartman@mail.zedat.fu-berlin.de>
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Subject: FreeBSD 9/ZFS: Striped Pool (2 disks) migrating to mirror (onto
 additional disk)
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I've got a problem. For performance reasons I use two 1TB harddrives as 
a single pool, and as far as I know, ZFS on recent FreeBSD 9/amd64 
treats suchs pools 'striped'. Well, I can measure a performance gain in 
writing and reading. Well, for backup, I use an additional 2TB disk, 
ZFS, compressed, the backup is done manually via rsync (i'm looking for 
more suitable simple backup solutions).
My question is: is it possible to migrate the two-disk pool without data 
loss into a mirrored pool by adding the one 2TB-disk?

Comments appreciated,
thanks in advance,

Oliver