ZFS unable to import pool

[Hugo Lombard]

On Wed, Apr 23, 2014 at 02:03:07PM +0200, Johan Hendriks wrote:
> 
> But you can force it....

True, I noted the hint from 'zpool add'.

That said, I'm not in the habit of forcing my will on tools.  I've seen
too many cases of people reporting breakage in tool X and then upon
further probing it turns out they indiscriminately used the '-f' to make
their immediate problem go away, and then some time later there's a lot
of tears over lost data. [1]

But I digress.

The point that I failed to make is that in my mind there's more to the
problem that started this thread than the original statement of:

  I have accidentally formatted one of the drives in exported ZFS pool. [2]

Having said that, in the process of trying to replicate the problem I've
learned a lot more about ZFS than I knew before the report, so for that
I'm grateful.

> If you force it, it will add a vdev not the same as the current
> vdev. So you will have a raidz1 and a single no parity vdev in the
> pool. If you destroy the single disk vdev then you will get a pool
> which can not be repaired as far as I know.

Thanks, that seems like ample reason to reinforce my dislike of invoking
the '-f' option on tools.


[1] There's no evidence at this point to my knowledge that the reporter
used '-f'.  I'm making a general statement.


[2] http://lists.freebsd.org/pipermail/freebsd-fs/2014-April/019339.html

-- 
Hugo Lombard
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