From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp2.cc.ic.ac.uk ([155.198.5.156]:59871 "EHLO smtp2.cc.ic.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775Ab0LMLnO (ORCPT ); Mon, 13 Dec 2010 06:43:14 -0500 Received: from squidward.hep.ph.ic.ac.uk ([155.198.211.86]) by smtp2.cc.ic.ac.uk with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.72) (envelope-from ) id 1PS6oB-0008Sl-Rd for linux-nfs@vger.kernel.org; Mon, 13 Dec 2010 11:43:11 +0000 Message-ID: <4D0606D0.4010702@imperial.ac.uk> Date: Mon, 13 Dec 2010 11:43:12 +0000 From: Tim Watts To: linux-nfs@vger.kernel.org Subject: Re: NooB Assitance with debugging NFSv4 client requested References: <4D024A8E.50407@imperial.ac.uk> <4D05F3E2.6090902@imperial.ac.uk> In-Reply-To: <4D05F3E2.6090902@imperial.ac.uk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Hmm, Wonder if this is a clue (not noticed this before, but running idmapd in the foreground, it just whined): rpc.idmapd: nfscb: read(/var/lib/nfs/rpc_pipefs/nfs/clnt0/idmap): No such file or directory (Repeated several times). I'm veering towards this issue being an idmap problem. Cheers tim On 13/12/10 10:22, Tim Watts wrote: > Bump - anyone :) > > Please note - I'm not requesting anyone fix a deeply obscure problem. > I'm a sysadmin - I'd just be really grateful for some pointers to help > me continue debugging this myself... > > Ta, > > Tim > > On 10/12/10 15:43, Tim Watts wrote: >> Hi, >> >> I have an NFSv4 client set up on Ubuntu 10.04.1 LTS x86. The NFSv4 >> server is running Centos 5.5 and we use MIT kerberos and LDAP for >> users/groups. This seems to work well with Centos 5.5 clients >> >> All works fine with my Ubuntu client, except after a while my client >> acts like it loses its authentication - symptom: home directory mount >> drops to "nobody" - I see the mount as "other" - no write access, can >> read files that have world read bit set etc. >> >> This can happen anytime between 48 hours and 2 hours after a full client >> reboot. It seems to be triggered by active use of thunderbird via the >> NFSv4 mounted home dir which suggests it may be load sensitive. >> >> When it happens, if I unmount my home dir (killing the desktop of >> course) , then remount the fault is cleared and I can work again. >> >> What doesn't work is just doing a kinit -f or restarting idmapd or gssd. >> >> I have run rpc.gssd in foreground debug mode and that doesn't say much >> during the problem times, ditto idmapd. We are using openldap for passwd >> and group lookups cached locally with nscd. >> >> I have tried upping kernel debugging: >> >> rpcdebug -m nfs -s vfs dircache lookupcache pagecache proc xdr file root >> callback client mount all >> >> but I'm not sure what I'm looking for. >> >> The symptoms feel like the kernel is losing the ticket or timing it out >> or possibly the ID mapping is failing - is there any way to examining >> the state of the kernel ticket cache or anything else I could be looking >> for? >> >> I am tempted to say this is a bug, possibly in the Ubuntu build, but I >> would like to investigate further. >> >> Any pointers much appreciated as to how I might isolate the fault >> further. >> >> Cheers >> >> Tim > > -- Tim Watts Linux Sysadmin, High Energy Physics, Imperial College London Tel: 020 759 47809