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Hi Wilko,

Ah, that's what I was afraid of. Looks like I'll have to implement the
"nomss" option for selected paths to get around that problem. Writing the
script will get around that for now. I suppose the script could be clever
enough to simply exec the "real" mssgwcmd if need be (based on the path
prefix). It's a hack but it will get around the problem until I have a
better solution.

Andy

On Tue, 23 Nov 2004, Wilko Kroeger wrote:

>
> Hello Andy
>
> I was reading the oss/ofs documentation last night and also thought
> that if I would write my own mmssgwcmd I could prevent xrootd from using
> the MSS. As you suggested (prefer) I will write a little script that
> implements the mmssgwcmd for the local file system.
> There still might be some issues because we use a mixed setting on the
> bbrprod machine: the /prod area is using only the cache system but no
> HPSS, /store is using the cache system, does migration and might
> want to use a mmssgwcmd that access hpss. I have to think a little
> bit about this and what the implications are.
>
> Cheers,
>    Wilko
>
>
>
> On Tue, 23 Nov 2004, Andrew Hanushevsky wrote:
>
> > Hi Wilko,
> >
> > OK, it appears that you can't have your cake and eat it too. If you want
> > the special files to be created in the file system but don't want to use
> > the MSS for anything then you will need to write your own mmssgwcmd that
> > does the operations locally instead of remotely. This completely
> > documented in the ofs/oss manual under mssgwcmd. While it would be
> > possible to add an option to indicate that only special files shuld be
> > created and, otherwise, no MSS is being used; it would be faster to just
> > write a small perl script that implements the various commands that would
> > be directed to the MSS.
> >
> > It is apparent that dirlist should be done only locally (that that will
> > not give you the complete list of files but only those on disk). The rm,
> > mv, and create commands should probably do nothing more that return a zero
> > status code. I assume you also want these to occur locally. The statx
> > command, well, you have to decide what to do there. This gets called if
> > the file/dir does not exist on the local disk.
> >
> > Let me know which way you want to proceed. If you would like to write this
> > (prefered) or you want me to write the script.
> >
> > Andy
> >
> > On Mon, 22 Nov 2004, Wilko Kroeger wrote:
> >
> > >
> > > Hello Remi
> > >
> > > Your problem is due to the configuration of the xrootd servers.
> > > Trying to get an directory listing (/kanga/prod/s5/s4/s3/s2/s1 on
> > > bbrprod05), I see in the xrootd log file:
> > >
> > > 041122 23:34:55 059 XrootdXeq: User logged in as wilko.6750:18@noric06
> > > pudc: Error opening directory /kanga/prod/s5/s4/s3/s2/s1/; No such file or directory.
> > > 041122 23:34:55 059 oss_XrdOssMSS_Xeq: Unable to execute dlist; no such file or directory
> > > 041122 23:34:55 059 ofs_opendir: wilko.6750:18@noric06 Unable to open
> > > directory /prod/s5/s4/s3/s2/s1/; No such file or directory
> > >
> > > It looks to me that xrootd tries to check the file in HPSS and not on
> > > disk. I tried to get a dir listing from '/store/' and I get a
> > > directory listing from hpss.
> > >
> > > Andy: How to configure xrootd so that dir listings are done from a disk
> > > and not HPSS?
> > > Another question comes to my mind: What happens if I remove a file or
> > > directory? Does it get removed from HPSS ?
> > >
> > >
> > > Cheers,
> > >   Wilko
> > >
> > >
> > >
> > > On Mon, 22 Nov 2004, Remi Mommsen wrote:
> > >
> > > > Hi,
> > > >
> > > > I'm using today's cvs HEAD for XrdClientAdmin.
> > > >
> > > > I try to get a directory listing using the perl interface like:
> > > >
> > > > XrdClientAdmin::XrdInitialize("root://bbrprod05:1094/dummy", 0);
> > > > XrdClientAdmin::XrdDirList('/prod/sub5/');
> > > >
> > > > but I get:
> > > > 041122 22:25:03 001 Xrd: DirList Server
> > > > [bbrprod05.slac.stanford.edu:1094] did not return OK message for last
> > > > request.
> > > > 041122 22:25:03 001 Xrd: SendGenCommand Server declared error
> > > > 3011:Unable to open directory /prod/sub5/; No such file or directory
> > > >
> > > > while the directory is there:
> > > > [bbrprod05] ~ > ls -l /kanga/prod/sub5/
> > > > total 2
> > > > drwxr-sr-x   3 bbdatsrv bfactory     512 Nov 22 22:17 sub6
> > > >
> > > >
> > > >
> > > > Removing the directory fails, too:
> > > > XrdClientAdmin::XrdRmdir("/prod/sub5/sub6/sub7/");
> > > >
> > > > 041122 22:26:06 001 Xrd: Rmdir Server
> > > > [bbrprod05.slac.stanford.edu:1094] did not return OK message for last
> > > > request.
> > > > 041122 22:26:06 001 Xrd: SendGenCommand Server declared error
> > > > 3010:Unable to remove /prod/sub5/sub6/sub7/; Not owner
> > > >
> > > >
> > > > Is this a server configuration problem (it occurs on all bbrprod0X
> > > > machines at SLAC), or is there a bug in the code?
> > > >
> > > > Cheers,
> > > > 		Remi
> > > >
> > > >
> > > > ---------------------------------------------------------------------
> > > > Truth decays into beauty, while beauty soon becomes merely charm.
> > > > Charm ends up as strangeness, and even that doesn't last, but up and
> > > > down are forever.                                         (Anonymous)
> > > >
> > > > *********************************************************************
> > > > Remigius K. Mommsen                 e-mail: [log in to unmask]
> > > > University of California, Irvine       URL:    http://cern.ch/mommsen
> > > > c/o SLAC                             voice:        ++1 (650) 926-3595
> > > > 2575 Sand Hill Road #35                fax:        ++1 (650) 926-3882
> > > > Menlo Park, CA 94025, US              home:        ++1 (650) 233-9041
> > > > *********************************************************************
> > > >
> > > >
> > >
> >
>