degraded zfs slowdown

[Randy Bush]

>> as the ghostly bad drive does not have a unique name, [how] can i tell
>> zfs to remove it for the moment?
> Have you tried running a scrub on the pool and THEN trying to offline
> and detach (zpool commands, not physical actions) the ghost drive?

    psg.com:/root# zpool scrub tank
    psg.com:/root# zpool status
      pool: tank
     state: DEGRADED
    status: One or more devices could not be used because the label is missing or
	    invalid.  Sufficient replicas exist for the pool to continue
	    functioning in a degraded state.
    action: Replace the device using 'zpool replace'.
       see: http://www.sun.com/msg/ZFS-8000-4J
     scrub: scrub in progress for 0h0m, 0.00% done, 169h12m to go
    config:

	    NAME        STATE     READ WRITE CKSUM
	    tank        DEGRADED     0     0     0
	      mirror    DEGRADED     0     0     0
		twed1   FAULTED      0     3     0  corrupted data
		twed1   ONLINE       0     0     0

    errors: No known data errors

still do not know how to detach bad drive as it does not have a unique
name

randy

> Note: when adding the replacement drive, remember to ATTACH the drives
> together. If you ADD the new drive, you will end up with a stripe, not
> a mirror.

ack.  thanks.

randy