[OpenAFS] Re: File contents change when copying into AFS with rsync

[Andrew Deason]

On Wed, 26 Jan 2011 12:45:13 -0800
"Dorian Taylor (Lists)" <dorian.taylor.lists@gmail.com> wrote:

> I've just begun teaching myself about OpenAFS, having installed it
> (1.4.12.1+dfsg-2, Ubuntu Maverick i386)

Does this describe both the client and fileserver?

> The two times I've bulk-loaded data into my new AFS cell with rsync,  
> I've been paranoid enough to generate checksums of the files on both  
> sides. In both several-gigabyte batches there was exactly one file  
> with exactly one four-byte difference. What I'd like hopefully are  
> some ideas for narrowing down if this is an rsync thing, an OpenAFS  
> thing, or something else (cheap memory, gremlins, etc.).

Was the difference in the same/similar spot both times? Could you share
the actual/expected byte sequence?

...did you verify the checksum and/or contents on the source before
_and_ after the transfer?

> Currently my strategy is to try different methods of copying over the  
> next several days (as it will take days) until a clear culprit becomes  
> evident.

Before doing that, you may want to see whether it is the data on the
server that is 'bad', or if the clients are reporting different data to
the application. You can do this by trying to read the file after
flushing it from the cache ('fs flush'), reading from different clients,
or reading it directly from the vicepX partition on the fileserver (ask
if you want to know how to do this).

-- 
Andrew Deason
adeason@sinenomine.net