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Date: Tue, 11 Jan 2011 14:23:59 +0100
From: Miroslav Lachman <000.fbsd@quip.cz>
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To: Dan Langille <dan@langille.org>
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Cc: freebsd-stable <freebsd-stable@freebsd.org>,
	John Hawkes-Reed <hirez@libeljournal.com>
Subject: Re: ZFS - hot spares : automatic or not?
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Dan Langille wrote:
> On 1/4/2011 11:52 AM, John Hawkes-Reed wrote:

[...]

>> As far as our testing could discover, it's not automatic.
>>
>> I wrote some Ugly Perl that's called by devd when it spots a drive-fail
>> event, which seemed to DTRT when simulating a failure by pulling a drive.
>
> Without such a script, what is the value in creating hot spares?

IMHO hot spares are totally useless in the current state (in FreeBSD).

I think there should be some strong warning somewhere (in man zpool?). 
Some users can be misleaded otherwise.

Miroslav Lachman