ZFS export then import a pool failed

Jon Chesterfield

New Member

Messages: 2


I'm running FreeBSD 9.0-RELEASE, installed years ago. It mostly functions as network attached storage. The majority of my data is on a single two disk mirror.

This week I'm trying to back up said mirror to a new usb hard drive. I created a zpool on the device, optimistically enabled compression, then pushed my data to it using rsync. This took ages (USB2) but otherwise worked. I ran scrub on the new backup, came back clean. All good.

I then ran zpool export backup, waited a few minutes, then ran zpool import backup. And now I'm posting here.

micro# zpool import backup

cannot import 'backup': one or more devices is currently unavailable

micro# zpool import 

  pool: backup

    id: 11413961023716631030

 state: FAULTED

status: One or more devices contains corrupted data.

action: The pool cannot be imported due to damaged devices or data.

  see: http://www.sun.com/msg/ZFS-8000-5E


    backup                 FAULTED  corrupted data

      7199744602161691224  UNAVAIL  corrupted data

I've tried '-f' and '-F' as well. I'd like to know what else is worth trying. Thanks

Jon Chesterfield

New Member

Messages: 2

Thanks for your response. I'm reluctant to upgrade the operating system without a viable backup in place.

On the grounds that it's all going wrong anyway, I wrote 8m/bytes of zeros to the start of the drive (expecting to blow away the partition table) and discovered that it can now be imported.

micro# zpool status

  pool: backup

state: ONLINE

status: One or more devices has experienced an unrecoverable error.  An

        attempt was made to correct the error.  Applications are unaffected.

action: Determine if the device needs to be replaced, and clear the errors

        using 'zpool clear' or replace the device with 'zpool replace'.

  see: http://www.sun.com/msg/ZFS-8000-9P

I'll scrub and see how that goes...

Scrub complete, 7 files damaged, copied across. Scrub again and all clear.
Repeated the attempt to export, then import. This time I used the numeric ID as hinted at in some other thread.

The backup appears to be successful. My faith is somewhat shaken, but I am confident enough to update to a newer freebsd install over the coming days.

Thank you all
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