zfs discuss - Nov 2007 - Missing zpool devices, what are the options

We had a ''windoze'' zpool on two internal disks. It had a
number of zvols
which
were ISCSI''d out to a few hosts. This has been in and running for some 
months.

Recently someone added some external SE6140 LUNs to the zpool as well, 
and last
friday those LUNs were deleted from the SE6140 itself, as far as I know they
aren''t recoverable at all.

Is it possible to tell ZFS to forget those SE6140 LUNs ever belonged to the
zpool? I know that ZFS will have probably put some user data on them, but if
there is a possibility of recovering any of those zvols on the zpool 
it''d really
help a lot, to put it mildly. My understanding is all the metadata will 
be spread
around and polluted by now, even after a few days of the SE6140 LUNs 
being linked,
but I thought I''d ask.

Any attempt to remove the devices just produces a zpool unavailable 
message. The
machine is running Sol 11 snv_64a on a T2000.

ta,
Mark.

  pool: windoze
 state: UNAVAIL
status: One or more devices could not be opened.  There are insufficient
        replicas for the pool to continue functioning.
action: Attach the missing device and online it using ''zpool
online''.
 scrub: none requested
config:

        NAME                                       STATE     READ WRITE 
CKSUM
        windoze                                    UNAVAIL      0     
0     0  insufficient replicas
          c2t2d0s0                                 ONLINE       0     
0     0
          c2t3d0s0                                 ONLINE       0     
0     0
          c7t600A0B80002AD18400000C9347212598d0s0  UNAVAIL      0     
0     0  cannot open
          c7t600A0B80002A096000000C2E4721250Fd0s0  UNAVAIL      0     
0     0  cannot open

Quoth Mark Ashley on Mon, Nov 12, 2007 at 11:35:57AM
+1100:
> Is it possible to tell ZFS to forget those SE6140 LUNs ever belonged to the
> zpool? I know that ZFS will have probably put some user data on them, but
if
> there is a possibility of recovering any of those zvols on the zpool 
> it''d really help a lot, to put it mildly. My understanding is all
the
> metadata will be spread around and polluted by now, even after a few
> days of the SE6140 LUNs being linked, but I thought I''d ask.
No.  I believe this is 4852783, "reduce pool capacity", which
hasn''t
been implemented yet.  (I don''t know whether it''s being worked
on.)
I think your best bet is to copy off any data you can get to, and
recreate the pool.


David