Analysis of disk file block with ZFS checksum error

[Joe Peterson]

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}@

@$${138B00{@
@$$}138B00}@

@$${138B01{@
[181:^80(^91^2146F)]
@$$}138B01}@

@$${138B02{@
@$$}138B02}@

@$${138B03{@
[2C:^80(^91^2146F)]
@$$}138B03}@

@$${138B04{@
@$$}138B04}@

.
.
.

@$${138B8B{@
<(21470=Thu Jan 24 23:20:58 2008)>
[117:^80(^91^21470)]
@$$}138B8B}@

.
.
.

@$${138C18{@
<(21472=1201242069)>[-2:^80(^82^85)(^83^1B5)(^84=b)(^85=1)(^86=0)(^87=0)
    (^88=0)(^89^2146C)(^8A=)(^8B=40)(^8C=2e)(^8D^84)(^8E=0)(^90^21472)
    (^91^21460)]
@$$}138C18}@

@$${138C19{@
<(21473=a72f78)>[2:^80(^89^21473)]
@$$}138C19}@

@$${138C1A{@
@$$}138C1A}@

.
.
.


and more of the same.  Note the date string.  There are several like
that.  Anyone recognize this text format?

				-Joe