Return-Path: Received: from daytona.panasas.com ([67.152.220.89]:58034 "EHLO daytona.panasas.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753198Ab0KUNlV (ORCPT ); Sun, 21 Nov 2010 08:41:21 -0500 Message-ID: <4CE9217E.6090002@panasas.com> Date: Sun, 21 Nov 2010 15:41:18 +0200 From: Boaz Harrosh To: Hiroyuki Sato CC: linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org Subject: Re: [Q] I tried to mount nfs_server:/mnt volume, but It mounted another volume. References: In-Reply-To: Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On 11/21/2010 02:23 PM, Hiroyuki Sato wrote: > Hello lists > > OS: CentOS 5.5 > kernel: 2.6.36 rebuild myself. > > > I'm trying to test NFS/RDMA. > I tried to mount nfs_server:/mnt volume on on nfs_client > but It mounted nfs_server:/nfstest volume > > note: /nfstest is tmpfs > > this is mount output > tmpfs on /nfstest type tmpfs (rw,size=4g) > /dev/sdb1 on /mnt type ext3 (rw) > > Is this bug?? > > NFS server config > > # ls -1 /mnt > This_is_mnt_volume > > # ls -1 /nfstest > This_is_nfstest_volume > > # cat /etc/exports > /nfstest 192.168.100.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash) > /mnt 192.168.100.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash) > You must not have two exports with fsid=0. First one is picked. nfs4 will only export a single name space point, other exports are subdirs of that root export. (use bind mounts to present a single directory tree) NFSv4 exports on linux ~~~~~~~~~~~~~~~~~~~~~~ NFSv4 no longer has a separate "mount" protocol. Instead of exporting a number of distinct exports, an NFSv4 client sees the NFSv4 server's exports as existing inside a single filesystem, called the nfsv4 "pseudofilesystem". On the current linux implementation, the pseudofilesystem is a single real filesystem, identified at export with the fsid=0 option. In the example above, we exported only a single filesystem, which the client mounted as "/". You can provide clients with multiple filesystems to mount, producing NFSv3-like-behavior, by creative use of mount --bind. For example, you could export /usr/local/bin to clients as /bin and /usr/local/etc as /etc as follows: mkdir /export mkdir /export/bin mkdir /export/etc mount --bind /usr/local/bin /export/bin mount --bind /usr/local/etc /export/etc exportfs -ofsid=0,insecure,no_subtree_check *:/export exportfs -orw,nohide,insecure,no_subtree_check *:/export/bin exportfs -orw,nohide,insecure,no_subtree_check *:/export/etc Note that the paths returned by the "showmount" program are meaningful only to clients using nfs versions 2 and 3; in the above example, "showmount" will list the paths /export, /export/bin/, and /export/etc, but nfsv4 clients should mount yourserver:/, yourserver:/bin, or yourserver:/etc. Boaz > > # modprobe svcrdma > > # /sbin/service nfs start > > # echo rdma 20049 > /proc/fs/nfsd/portlist > > > Client Setting > > /sbin/modprobe xprtrdma > /sbin/mount.rnfs 192.168.100.231:/mnt /mnt -i -o rdma,port=20049 > > # ls -1 /mnt > This_is_nfstest_volume > > NFS Server log > sysctl -w sunrpc.nfsd_debug=1023 > > Nov 21 20:47:37 dell1435 mountd[3575]: authenticated mount request > from 192.168.100.232:766 for /mnt (/mnt) > Nov 21 20:47:37 dell1435 mountd[3575]: /nfstest and /mnt have same > filehandle for 192.168.100.0/255.255.255.0, using first > Nov 21 20:48:55 dell1435 mountd[3575]: authenticated unmount request > from 192.168.100.232:912 for /mnt (/mnt) > Nov 21 20:48:55 dell1435 mountd[3575]: authenticated unmount request > from 192.168.100.232:913 for /mnt (/mnt) > Nov 21 20:49:00 dell1435 mountd[3575]: authenticated unmount request > from 192.168.100.232:917 for /mnt (/mnt) > Nov 21 20:49:16 dell1435 mountd[3575]: authenticated mount request > from 192.168.100.232:865 for /mnt (/mnt) > Nov 21 21:02:22 dell1435 mountd[3575]: authenticated unmount request > from 192.168.100.232:955 for /mnt (/mnt) > Nov 21 21:02:26 dell1435 mountd[3575]: authenticated mount request > from 192.168.100.232:884 for /mnt (/mnt) > Nov 21 21:02:26 dell1435 kernel: nfsd: exp_rootfh(/mnt > [ffff88011f586740] 192.168.100.0/255.255.255.0:sdb1/2) > > > -- > Hiroyuki Sato > -- > 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