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To: "M. Warner Losh" <imp@bsdimp.com>
In-reply-to: Your message of "Sat, 18 Feb 2006 10:21:45 MST."
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Date: Sat, 18 Feb 2006 09:35:24 -0800
From: Bakul Shah <bakul@BitBlocks.com>
Cc: hackers@freebsd.org
Subject: Re: Bad block -> file mapping 
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> I have a hard disk that's been in service a long time.  I recently
> installed the SMART monitoring tools.  On occasion, I get reports of
> LBAs it can't read.  I'd like to map the LBA to an actual file in the
> file system, if possible.  Does anybody have any tools that can help
> me with this?
> 
> I know I need to get a new disk.  In the mean time, I need to cope
> with these errors in a sane manner...
> 
> Warner
> 
> P.S.  Here's a sample report:
> 
> Num  Test_Description    Status           LifeTime(hours)  LBA_of_first_error
> # 1  Extended offline    Completed: read failure     8949         65818210
> # 2  Short offline       Completed without error     8948         -

Wouldn't bad block forwarding by the disk take care of this?
Generally you want the read of a bad block to return an error
but if you write the block the disk will automatically remap
this block to one of the spare blocks.

What exactly are you trying to do by mapping a bad block to a
file?  Nevertheless may be fsdb will help?  You still need to
map LBA to the slice/partition offset.