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Date: Fri, 8 Feb 2008 15:02:08 -0800
From: Alfred Perlstein <alfred@freebsd.org>
To: Joe Peterson <joe@skyrush.com>
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Cc: freebsd-fs@freebsd.org, Mark Day <mday@apple.com>,
	freebsd-stable@freebsd.org
Subject: Re: Analysis of disk file block with ZFS checksum error
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* Joe Peterson <joe@skyrush.com> [080208 14:58] wrote:
> Mark Day wrote:
> > Based on the subset of data you posted, the bad data looks like ASCII
> > text.
> > The bad data from offset a0000 to a000f is:
> >
> > ${138AFE{@
> > @$$}1
> >
> > The bad data from offset af6c1 to af6c8 is:
> >
> > 392A9}@
> >
> > I don't recognize the content beyond that, but I'd guess that somehow
> > the
> > contents of some other file managed to overwrite that portion of the bad
> > file.  As for how that happened, I don't know.  But if someone
> > recognizes
> > where the bad content came from, that might be a clue.
> 
> 
> Gary/Mark,
> 
> Good eye!  Yes, it indeed does appear to be ASCII.  I *thought*
> something in the repetition when I originally did an od -a looked
> interesting.
> 
> I dumped the whole bad section as a string, and here's (partly) what I get:
> 
> ${138AFE{@
> @$$}138AFE}@
> 
> @$${138AFF{@
> [A3:^80(^91^2146F)]
> @$$}138AFF}@
> 
> @$${138B00{@

Looks like terminal output/codes that have been stripped...

-Alfred