From: "Murata, Dennis" Subject: Re: [NFS] export dir thru 2 diff path names Date: Mon, 10 Nov 2008 10:11:59 -0800 Message-ID: <620E93B2E5CC3B46BD811165E3335B8702F374A0@0461-its-exmb02.us.saic.com> References: <478B90A1.5000900@bnl.gov><1200330387.7470.11.camel@heimdal.trondhjem.org><478B9A64.5030903@bnl.gov> <49147E79.6000508@bnl.gov><20081109155831.GA24508@fieldses.org> <49185984.8010500@bnl.gov><20081110164947.GA17050@fieldses.org> <491869F0.1000505@bnl.gov> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: "Sev Binello" , "J. Bruce Fields" , Return-path: Received: from neil.brown.name ([220.233.11.133]:55293 "EHLO neil.brown.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754388AbYKJSK0 (ORCPT ); Mon, 10 Nov 2008 13:10:26 -0500 Received: from brown by neil.brown.name with local (Exim 4.69) (envelope-from ) id 1KzbDU-00081T-9J for linux-nfs@vger.kernel.org; Tue, 11 Nov 2008 05:10:24 +1100 In-Reply-To: <491869F0.1000505-IGkKxAqZmp0@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: I just tested this on a SL4.7 (RHEL 4.7 variant) using a RHEL 4.4 nfs server. I did get the messages from exportfs about duplicate export entries. On the client I was able to mount both the symlink and the actual directory. They look like separate mounts. There are two entries in /proc/mounts and in /etc/mtab, one with the actual directory path, one with the symlink path. I am using autofs to mount the directories, not hardcoded. Are you using newer distributions? What problems will I cause by doing this? I am using the symlink path as the installation path for an application. The idea is a newer version can be installed into a different directory, then after testing the symlink will be changed to the new installation. Other applications that reference the application will always use the symlink path, as well as any user scripts. Wayne > -----Original Message----- > From: linux-nfs-owner@vger.kernel.org > [mailto:linux-nfs-owner@vger.kernel.org] On Behalf Of Sev Binello > Sent: Monday, November 10, 2008 11:06 AM > To: J. Bruce Fields; nfs@lists.sourceforge.net > Subject: Re: [NFS] export dir thru 2 diff path names > > J. Bruce Fields wrote: > > On Mon, Nov 10, 2008 at 10:55:48AM -0500, Sev Binello wrote: > > > >> Well the simplest approach doesn't work. > >> i.e put symb link and actual path in the export file & try > exporting > >> it Exportfs dereferences the link and states that > duplicates are not allowed. > >> > > > > OK, makes sense. > > > > You could mount --bind the filesystem at the other location > instead of > > symlinking. > > > > The filehandles given to the client will be the same across the two > > exports. If you mount both from the same client, behavior may vary > > across different clients (for example, as to whether they > attempt to > > share caches between the two), but I think it'd work. > > > > (The question "why??!!??" does come to mind, though.) > > > > > Need to make a path change to how file systems are mounted > and exported on the servers This then required a wholesale > change to clients so they mount the correct path. > Not an issue for linux. > But since we don't administer windows pcs and they also mount > the same file system, wanted to see if we could let them stay > the way they were for now. > > We're just going to go ahead and have to coordinate this > with windows guys. > > -Sev > > --b. > > > > > >> -Sev > >> > >> J. Bruce Fields wrote: > >> > >>> On Fri, Nov 07, 2008 at 12:44:25PM -0500, Sev Binello wrote: > >>> > >>> > >>>> Can anyone tell me if it's ok to export the same file system > >>>> through 2 different paths ( one is a link) ? > >>>> > >>>> > >>> I actually don't know. You could try it and tell us what > you find > >>> out.... > >>> > >>> If you're exporting something *containing* the symlink > and expecting > >>> the client to traverse into the filesystem, be aware that > symlinks > >>> over NFS are actually interpreted (and followed) on the > client--so > >>> they're interpreted as *client-side* paths, not server-side. > >>> > >>> If the path you're exporting is itself a symlink--it probably > >>> depends on how nfs-utils treats symlinks found in > /etc/exports. I'd > >>> have to try it or check the code. > >>> > >>> Another way to export the filesystem in two different > places would > >>> be with mount --bind. > >>> > >>> --b. > >>> > >>> > >> -- > >> > >> Sev Binello > >> Brookhaven National Laboratory > >> Upton, New York > >> 631-344-5647 > >> sev-IGkKxAqZmp0@public.gmane.org > >> > >> > > > -------------------------------------------------------------- > ----------- > This SF.Net email is sponsored by the Moblin Your Move > Developer's challenge Build the coolest Linux based > applications with Moblin SDK & win great prizes Grand prize > is a trip for two to an Open Source event anywhere in the > world http://moblin-contest.org/redirect.php?banner_id=100&url=/ > _______________________________________________ > NFS maillist - NFS@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/nfs > _______________________________________________ > Please note that nfs@lists.sourceforge.net is being discontinued. > Please subscribe to linux-nfs@vger.kernel.org instead. > http://vger.kernel.org/vger-lists.html#linux-nfs > > -- > To unsubscribe from this list: send the line "unsubscribe > linux-nfs" in the body of a message to > majordomo@vger.kernel.org More majordomo info at > http://vger.kernel.org/majordomo-info.html > ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs _______________________________________________ Please note that nfs@lists.sourceforge.net is being discontinued. 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