From: Neil Brown Subject: Re: fsid syntax Date: Thu, 8 Aug 2002 06:31:01 +1000 Sender: nfs-admin@lists.sourceforge.net Message-ID: <15697.33669.398331.848444@notabene.cse.unsw.edu.au> References: <200208071711.00712.bernd-schubert@web.de> <200208071830.54734.bernd-schubert@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Trond Myklebust , nfs@lists.sourceforge.net Return-path: Received: from tone.orchestra.cse.unsw.edu.au ([129.94.242.28]) by usw-sf-list1.sourceforge.net with smtp (Exim 3.31-VA-mm2 #1 (Debian)) id 17cXS3-0004m0-00 for ; Wed, 07 Aug 2002 13:30:39 -0700 Received: From notabene ([129.94.242.45] == bartok.orchestra.cse.unsw.EDU.AU) (for ) (for ) (for ) By tone With Smtp ; Thu, 8 Aug 2002 06:30:21 +1000 To: Bernd Schubert In-Reply-To: message from Bernd Schubert on Wednesday August 7 Errors-To: nfs-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Unsubscribe: , List-Archive: On Wednesday August 7, bernd-schubert@web.de wrote: > On Wednesday 07 August 2002 17:26, Trond Myklebust wrote: > > The fsid is a number, not a device. In principle you can set it to any > > number you like as long as you keep it consistent over reboots. > > > > One suggestion is to use the device major/minor number in the format > > minor + (major * 256). (That's what nfsd uses by default for block > > devices.) > > > > Cheers, > > Trond > > > > > > Uh, good that I asked for this, so I was completely wrong. > > Is there a way to get the current fsid (after a reboot on Friday the fsid will > change and I don't want to reboot our clients) ? Or is it simply the fsid of > e.g. /dev/sdb, so that I can get it with statfs() ? > > Thanks for your help, Sorry, you cannot do that. The filehandles created with fsid=foo are different from any filehandle created without fsid=. If you want to change the device on the server what you need to do is: 1/ well in advance, add an 'fsid=42'(*) export option. Clients using old file handles will still work. Clients that subsequently mount will get new-style file handles. 2/ At your convenience, remount the filesystem on all clients, either by umount/mount or reboot or whatever. 3/ When all, or enough, clients have remounted, you can safely change the device number without affecting clients. (*) I really don't think that basing the fsid on the device number is at all sensible. Afterall, that is what we are trying to avoid. Just pick a number, any number. 1 for the first filesystem, 2 for the second. Your age for the filesystem storing you home directory. 42 for the filesystem storing the Great Question of Life, The Universe, and Everything. NeilBrown > > Bernd > > > ------------------------------------------------------- > This sf.net email is sponsored by:ThinkGeek > Welcome to geek heaven. > http://thinkgeek.com/sf > _______________________________________________ > NFS maillist - NFS@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/nfs ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs