From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andreas Steinmetz Subject: Re: Odd data corruption problem with LVM/ReiserFS Date: Mon, 21 Feb 2005 12:37:53 +0100 Message-ID: <4219C811.5070906@domdv.de> References: <93ca3067050220212518d94666@mail.gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit In-Reply-To: <93ca3067050220212518d94666@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Alex Adriaanse Cc: linux-kernel@vger.kernel.org, reiserfs-list@namesys.com Alex Adriaanse wrote: > As far as I can tell all the directories are still intact, but there > was a good number of files that had been corrupted. Those files > looked like they had some chunks removed, and some had a bunch of NUL > characters (in blocks of 4096 characters). Some files even had chunks > of other files inside of them! I can second that. I had the same experience this weekend on a md/dm/reiserfs setup. The funny thing is that e.g. find reports I/O errors but if you then run tar on the tree you eventually get the correct data from tar. Then run find again and you'll again get I/O errors. > I did a reiserfsck (3.6.19) on /var, which did not report any problems. You need to run 'reiserfsck --rebuild-tree' and see what happens :-( > Anyway, what do you guys think could be the problem? Could it be that > the LVM / Device Mapper snapshot feature is solely responsible for > this corruption? (I'm sure there's a reason it's marked > Experimental). I don't think so - I changed from reiserfs to ext3 without changing the underlying dm/raid5 and this seems to work properly. I can furthermore state that reiserfs without dm/md does work correctly as I use reiserfs on a ieee1394 backup disk (that saved me from terrible trouble). Currently I can only warn to not use reiserfs with dm/md on 2.6. -- Andreas Steinmetz SPAMmers use robotrap@domdv.de