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Date: Fri, 19 Aug 2011 19:57:19 -0400
From: Diane Bruce <db@db.net>
To: Dan Langille <dan@langille.org>
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Cc: freebsd-stable@freebsd.org
Subject: Re: bad sector in gmirror HDD
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On Fri, Aug 19, 2011 at 04:50:01PM -0400, Dan Langille wrote:
> System in question: FreeBSD 8.2-STABLE #3: Thu Mar  3 04:52:04 GMT 2011
> 
> After a recent power failure, I'm seeing this in my logs:
> 
> Aug 19 20:36:34 bast smartd[1575]: Device: /dev/ad2, 2 Currently unreadable (pending) sectors
> 

Personally, I'd replace that drive now. 

> Searching on that error message, I was led to believe that identifying the bad sector and
> running dd to read it would cause the HDD to reallocate that bad block.

No, as otherwise mentioned (Hi Jeremy!) you need to read and write the
block. This could buy you a few more days or a few more weeks. Personally,
I would not wait. Your call.
 
> Comments?
...
> Dan Langille - http://langille.org

- Diane
-- 
- db@FreeBSD.org db@db.net http://www.db.net/~db
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