How to destroy a zpool that can no longer be imported?

[Arthur Chance]

On 10/03/2014 14:36, Dave B wrote:
> If you don't mind loosing everthing on the physical disk(s)...
>
> 	"DBAN"
>
> Darik's Boot and Nuke.  http://sourceforge.net/projects/dban/
>
> Unlike Gpart (and GParted) this will truly errase the disk.
>
> What you end up with a truly clean, and able to be used for whatever you want
> afterwards, with no odd problems.
>
> I found GParted in particular, though it destroys the partition tables OK, it does
> not remove the data on disk that was in the partition.   As a result, I had
> terrible troubles a while ago, getting FBSD 9.2 to reload, after I seriously
> screwed something up.  GParted didn't do the job, I kept getting strange lib
> errors during the reinstall (from CD.)
>
> DBAN did the job, but it does take time, as it writes random noise to the entire
> physical disk, sector by sector.   The re-install after that, just worked, no errors.
>
> The price is right, but take care, once let loose, that's it, there is no turning
> back.

If all you want to do is clear a disk in order to reinstall it, doing

dd if=/dev/zero of=$DISK bs=1g

(possibly from a live CD/DVD) is quicker and doesn't require you to 
download and burn an extra ISO.