ZFS unable to import pool

[Jordan Hubbard]

If you added a single disk to a pool, you have no choice but to destroy the pool and start over.  The single disk will essentially degrade the performance of the whole pool, because it represents a unique (100Mb/sec, typical) transaction group now, and if you lose that one disk you will also lose the entire pool since it has no redundancy.

This is a common mistake people make with ZFS, and it sucks, but block pointer rewrite was never implemented so that’s just the way it is, too.  That’s another reason for FreeBSD-based front-ends to ZFS like FreeNAS.  The GUI adds some seat-belts to prevent users from trivially doing things like that.  On the command line, all bets are off.

- Jordan

On Apr 23, 2014, at 7:09 PM, Gena Guchin <ggulchin at icloud.com> wrote:

> Looking though the history, i DID add that disk ada7 (!) to the pool, but I added it as a separate disk. I wanted to re-add the disk to the storage pool, but it added as a new disk…
> this does help a lille..
> 
> 
> anything I can do now? 
> can I remove that vdev?