From owner-freebsd-questions  Wed Jun 13  5:50:14 2001
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Date: Wed, 13 Jun 2001 13:49:53 +0100 (BST)
From: George Reid <greid@FreeBSD.org>
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To: Nick Barnes <Nick.Barnes@pobox.com>
Cc: questions@FreeBSD.org
Subject: Re: interpreting UFS hard error messages 
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On Wed, 13 Jun 2001, Nick Barnes wrote:

> I know that, and I said as much in my original message.  However, this
> is not a critical machine and I'm happy to keep it running until the
> disk actually dies (in my experience this can be months rather than
> days).  Also I would like to improve my understanding of the
> filesystem and of messages such as this.

The message you quoted was NOT a filesystem error message; it was a
physical disk error. The same error will occur if you use UFS, ext2fs or
any other disk-backed filesystem. It is a message from the ATA system, not
the filesystem.

If you want to improve your understanding of the filesystem, there are n
papers and books detailing various aspects of it.

> 4. Are there any tools for exploring a filesystem (e.g. figuring out
>    which blocks belong to a file, or which file owns a block)?  How
>    about tools for disk verification?  I've found dumpfs(8).

I don't have time to check your sector calculations, but you may want to
check out the diskcheckd project. IIRC you should find it linked from:

	http://people.freebsd.org/~ben/

--
+-------------------+---------------------+
|    George Reid    |  FreeBSD Committer  |
|  +44 7740 197460  |  greid@FreeBSD.org  |
+-------------------+---------------------+


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