re-adding a replacement into a pool of mirrors

[Andrew Snow]

Randy Bush wrote:
>>> # zpool attach -f tank da0s3 da1s3
>>> cannot attach da1s3 to da0s3: permission denied
>> I think this stage should be working, unless something else in the 
>> system is already using da1s3 or has it opened.  Can you check through 
>> your system to see if any other parts of eg. geom have decided to take 
>> da1s3 for their purposes?
> 
> not that i can see.

It might be worth zeroing the whole disk with dd if=/dev/zero 
of=/dev/da1s3 bs=64k, and then see if you can re-attach.