zfs discuss - Dec 2009 - Upgrading a volume from iscsitgt to COMSTAR

Hi, I have a zfs volume that''s exported via iscsi for my
wife''s Mac to
use for Time Machine.

I''ve just built a new machine to house my "big" pool, and
installed
build 129 on it.  I''d like to start using COMSTAR for exporting the 
iscsi targets, rather than the older iscsi infrastructure.

I''ve seen quite a few tutorials on how to use COMSTAR for new volumes 
(and a few mentions of the shareiscsi=stmf).  I''ve seen some talk about
how the old infrastructure used to use the first 64K of the volume for 
the iscsi information (and that COMSTAR uses the ZFS metadata store.)

What I haven''t found is a set of steps for taking a volume from the old
way of doing things to the new.  There are hints (e.g., here: 
https://opensolaris.org/jive/thread.jspa?threadID=115078), but no 
concrete set of steps.

Despite the ease of use of ZFS, I presume that it''s not as simple as
saying:

zfs set shareiscsi=stmf <volume>

because a) it''s not clear to me that that setting for shareiscsi will
do
the same magic as shareiscsi=on used to do, and b) there''s that 
initial-64K-problem which I assume will make the Mac throw a wobbly when 
trying to mount the file system that''s on the volume.

Any advice on how to do this?  There''s plenty of room to create a new 
volume and dd over the data (suggestions for the skip parameter to dd 
welcome, though!) if that''s the only way.

Once I figure this out, I''ll be happy to write it up for my blog, which
can then be pointed to when this comes up again.

Thanks in advance,

Steve
-- 
Stephen Green                      //   Stephen.Green at sun.com
Principal Investigator             \\   http://blogs.sun.com/searchguy
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