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Date: Fri, 30 Aug 2013 10:17:11 +0200
From: Maurizio Vairani <maurizio.vairani@cloverinformatica.it>
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To: Andriy Gapon <avg@FreeBSD.org>
Subject: Re: Boot problem if a ZFS log device is missing
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On 29/08/2013 11.01, Andriy Gapon wrote:
> on 29/08/2013 11:27 Maurizio Vairani said the following:
>> I am able to boot the PC without a cache device but not without a log device. Why ?
> The log could potentially contain uncommitted entries.  Without the log device
> there is no knowing if it did or did not.  And if it did then the pool is
> inconsistent state without the log device and so it can not be imported.
>
> The cache is not persistent and so there is nothing needed from it upon a boot.
>
Thank you for the clear and concise reply.

Yesterday I have done some test. If I remove the stick from the USB 
port, before the shutdown the PC, it  don't crash but continues to 
works. Then  I am able to reboot the laptop without inserting the stick 
with a pool that works in degraded mode.

 From the end user point of view a PC should always boot, even with a 
missing ZFS log device.

Regards
Maurizio