From: Trond Myklebust Subject: Re: Problem with NFS and XEN Date: Fri, 08 May 2009 09:43:44 -0400 Message-ID: <1241790224.19651.40.camel@heimdal.trondhjem.org> References: <1241785441.19651.28.camel@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain Cc: linux-nfs@vger.kernel.org To: Roger Marcus Return-path: Received: from mail-out2.uio.no ([129.240.10.58]:45639 "EHLO mail-out2.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759586AbZEHNnr (ORCPT ); Fri, 8 May 2009 09:43:47 -0400 In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, 2009-05-08 at 15:11 +0200, Roger Marcus wrote: > Hi Trond, > > Thank you for your answer. > > exportfs does not report the individual directories that are mounted > on the exported directory, so I cannot use your script. > > on the nfsserver exports file: > /adir 192.168.11.129(rw,sync,no_subtree_check,crossmnt,no_root_squash) > > on the same machine: > mount -o loop virtual.iso virtualstuff > so now I have /adir/virtualstuff > > (which by the way, I can: umount virtualstuff immediately without > problem and it releases. > however, if I run XEN on the client, then the directory is permanently > locked, ie, umount virtualstuff > DOESN'T work again unless I run exportfs -ua killing all connections > to the server.) > > the nfs-client sees /adir/virtualstuff, since parent /adir is mounted. > When I run the virtualmachine within the virtualstuff directory (xm > create /adir/virtualstuff/config.cfg) > and then I destroy the virtualmachine (xm destroy /adir/virtualstuff/config.cfg) > I can never 'umount virtualstuff' from the nfsserver, even though no > one is accessing the directory > any more. > > So on the nfsserver I cannot umount virtualstuff. this is the bug. > > exportfs -ua kills nfs for everybody, and then I can run 'umount > virtualstuff', but this is not what I want. > exportfs -u nfsclient:/adir doesn't even work. I don't want this > variation because I might be running 2 virtual machines > in two subdirectories. > > question: is the fact that ;exportfs -u nfsclient:/adir' doesn't work a bug? > > What I want to be able to do is from the nfsserver side, 'umount > virtualstuff', which I can do if I > 1) never run XEN, or > 2) exportfs -ua. The latter command kills all clients attached to the server > so I cannot use this second command. > 3) the command 'exportfs -u nfsclient:/adir' doesn't work and this > might be a bug. I do not > want this variant since if I am running 2 virtual machines on the > nfsclient I would kill the other machine. > > In /proc/net/rpc/nfsd.export/content I see my virtualstuff > subdirectory referenced. Perhaps this > tells you something. > > Thank you in advance, > > Roger Marcus > Oh, you're using crossmnt to export the subdirectories? In that case, why doesn't just 'exportfs -f' suffice to allow you to unmount them? Trond