[OpenAFS] Problem with Excel "xls" documents on AFS

Karel Nykles knykles@civ.zcu.cz
Mon, 24 Oct 2011 10:58:24 +0200


Hi all,

We've tracked down an issue with OpenAFS windows clients (1.7.1 and
prior affected) and Microsoft Excel "xls" spreadsheets.

After a document is stored on AFS share, it is normaly accesible, after
some time, in this case whole night, the document can be still opened,
without problems, but after closing it without saving and opening from
other computer, it is "broken." On the first computer is it still
accessible for few minutes(propably stays in cache intact). The wrong
version must be produced propably between cache manager and file server,
unfortunatelly thats all we currently know.

Broken means some part of the document is filled with zeros, in our case
 it was about 20480B or similar.
Small documents with size about 20k are not affected.

Restarting service, flushing cache on the client has no effect, this
behavior  "needs its time". The document can be used with no problems,
unless it is stored on AFS for aproximately 6 or more hours.

I've tried to capture communication between Afs client and file server
with WireShark, when the document opens, after fetching data,  it shows
some storeDate requests to the fileserver,  with "fs setcrypt -crypt
off" I can see some parts of the  document, but not all of them are
transfered to the fileserver.

If the document is opened with Libre Office, this problem
does not occur. It is somehow specificaly related to Excel and AFS only.
Also the "xlsx" documents from Excel 2007 (opened in Excel 2003 with
compatibility pack) are not affected. Both Excel 2003 and Excel 2007 are
affected when working with "xls" documents.

Copying, and reading with other application than Excel has no effect.

Fileserver version is debian build 1.6.0.

Anybody has an idea what to do with this issue?

Best Regards,
Karel Nykles
University of West Bohemia