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Hello Derek


On Mon, 4 Apr 2005, Derek Feichtinger wrote:

> Hi,
>
> thanks for all the feedback, but since I was away last week I was only able to
> do another test today.
>
> I'm getting some unexpected behavior:
>
> I set up the system (config files are below) taking suggestions from your
> example setups.
>
> 1. I try to write a new file NEWFILE via the redirector => fails
>
>   $> xrdcp  fileA  root://lxn5219:1094//tmp/xrootd/newfile
>
>   Error accessing path/file for root://lxn5219:1094//tmp/xrootd/newfile

I think the problem is that the olbd doesn't know which path to use for
the new file.

The olbd needs the oss.cache (or equivalent the olb.cache) directive to
place the file.
I must admit that I don't exactly understand the whole logic but here are
the snippet from the data server configuration file that is used for
writing via the redirector.

#  directory /u1 (or different name) must exists but might not be used
   /tmp doesn't work)
oss.cache /u1

#   'inplace' means that the file is not put into the cache
oss.path  / inplace

xrootd.export /tmp

You can find the test configuration files in:
http://www.slac.stanford.edu/~wilko/kan/cfg/xrootd-ddev_1rdr.cf   (redirector)
http://www.slac.stanford.edu/~wilko/kan/cfg/xrootd-ddev_1.cf  (data server)

We will discuss this problem and make the configuration a little bit easier.

>
> 2. I try to write the same file NEWFILE to a leaf node => succeeds
>
>   $> xrdcp  fileA  root://lxn5207:1094//tmp/xrootd/newfile
>
> 3.  I try to overwrite NEWFILE with a smaller file via the redirector
>    =>now it succeeds, but the resulting file is the old file, where the start
> has been overwritten by the new smaller file.
>
>   $> xrdcp  ../fileBshort  root://lxn5219:1094//tmp/xrootd/newfile

The overwrite is a known problem and will be fixed. A wrong options
(kxr_force) is used for the open request.

Cheers,
  Wilko

>
>
> I'm using the new production version 20050328-0656 with xrdcp as a client.
> Reading files via the redirector is never a problem, but writing of new files
> still does not work for me.
>
> Thanks for any help,
> Derek
>
>
> These are the Config files:
> ==============================================================
> #
> # dataserver.cf
> #
> # xrootd
> xrootd.fslib /opt/xrootd/xrootd-20050328-0656/lib/arch/libXrdOfs.so
> xrootd.export /tmp/xrootd
>
> ofs.redirect target
>
> odc.manager  lxn5219
>
> # olbd
> olb.port 3121
> olb.path w /tmp/xrootd
> olb.subscribe lxn5219 3121
>
> oss.nostage
> oss.nocheck
> oss.nodread
> oss.nomig
> oss.alloc * * 80
> oss.fdlimit * max
> oss.path /tmp/xrootd
> ================================================================
> #
> # redirector.cf
> #
> # xrootd
> xrootd.fslib /opt/xrootd/xrootd-20050328-0656/lib/arch/libXrdOfs.so
> xrootd.export /tmp/xrootd
>
> odc.manager lxn5219 3121
> #odc.trace redirect
> odc.trace all debug
>
> ofs.trace all debug
> ofs.redirect remote
>
> # olbd
> olb.port 3121
> olb.path w /tmp/xrootd
> olb.allow host lxn5219.cern.ch
> olb.allow host lxn5207.cern.ch
> olb.allow host lxb1557.cern.ch
> olb.trace all debug
> ===================================================================
>
>
>