From: Trond Myklebust Subject: Re: Permission denied when mounting NFS (was okay before) Date: Fri, 26 Sep 2008 12:06:01 -0400 Message-ID: <1222445161.10150.4.camel@localhost> References: Mime-Version: 1.0 Content-Type: text/plain Cc: "Talpey, Thomas" , linux-nfs@vger.kernel.org To: howard chen Return-path: Received: from mail-out1.uio.no ([129.240.10.57]:41345 "EHLO mail-out1.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751878AbYIZQGG (ORCPT ); Fri, 26 Sep 2008 12:06:06 -0400 In-Reply-To: Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, 2008-09-26 at 23:57 +0800, howard chen wrote: > Hi, > > On Fri, Sep 26, 2008 at 11:25 PM, Talpey, Thomas > wrote: > > At 11:05 AM 9/26/2008, howard chen wrote: > > You didn't indicate what the client and server were, btw. > > client is 3, as I see when mount with verbose option: ... mount: > trying xxxx prog 100003 vers 3 prot udp port 2049 > > server should be also 3, default by CentOS 4.4, 64bit What does 'rpcinfo -p 10.10.10.1' give you? Also, 'showmount -e 10.10.10.1' Finally, what kind of filesystem are you exporting on /data0/tmp? > > > > Do you have multiple interfaces on the client? If the client routing > > originates from a different address than 10.10.10.2, then the server > > will deny it because you have specified a numerical address. > > Yes, both servers have interface for public IP, but as I can see the > 10.10.10.2 in /var/log/message of NFS server, so I think routing is > ok. > > > > > This isn't the source of the permissions error, but why are you doing > > a UDP mount, and with only three retries? Generally, TCP will perform > > better, and more robustly. Also, the "noatime" option is a no-op for > > the NFS client (servers are in charge of maintaining atime). > > I agree TCP is more robust, but isn't UDP will have a better performance? That depends. In my experience, the difference in performance on an unloaded network, then UDP will outperform TCP by ~10%. However, if you have a heavily loaded network with lots of dropped packets, then TCP will usually give much better performance than UDP. Trond