From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mondschein.lichtvoll.de ([194.150.191.11]:48243 "EHLO mail.lichtvoll.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755025Ab2FEJ5q convert rfc822-to-8bit (ORCPT ); Tue, 5 Jun 2012 05:57:46 -0400 From: Martin Steigerwald To: linux-btrfs@vger.kernel.org Subject: Re: Help with data recovering Date: Tue, 5 Jun 2012 11:57:45 +0200 Cc: Hugo Mills , Maxim Mikheev , Liu Bo References: <4FCC6F44.2030503@gmx.net> <20120604170422.GD15986@carfax.org.uk> <201206051155.14398.Martin@lichtvoll.de> (sfid-20120605_115658_819797_5AD8D2A2) In-Reply-To: <201206051155.14398.Martin@lichtvoll.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Message-Id: <201206051157.45469.Martin@lichtvoll.de> Sender: linux-btrfs-owner@vger.kernel.org List-ID: Am Dienstag, 5. Juni 2012 schrieb Martin Steigerwald: > Am Montag, 4. Juni 2012 schrieb Hugo Mills: > > On Mon, Jun 04, 2012 at 12:24:05PM -0400, Maxim Mikheev wrote: > > > I run through all potential tree roots. It gave me everytime > > > messages like these: > > > > > > parent transid verify failed on 3405159735296 wanted 9096 found > > > 5263 parent transid verify failed on 3405159735296 wanted 9096 > > > found 5263 > > […] > > > > The largest recovered data is 12Kb. > > > max@s0:~/btrfs-recovering./recovered$ ls -lahs 3728819929088 > > > total 28K > > > 4.0K drwxr-xr-x 3 root root 4.0K Jun 4 12:06 . > > […] > > > > What can I do next? > > > > > I'm out of ideas. > > > > At this point, though, you're probably looking at somebody writing > > > > custom code to scan the FS and attempt to find and retrieve anything > > that's recoverable. > > > > You might try writing a tool to scan all the disks for useful > > > > fragments of old trees, and see if you can find some of the tree > > roots independently of the tree of tree roots (which clearly isn't > > particularly functional right now). You might try simply scanning > > the disks looking for your lost data, and try to reconstruct as much > > of it as you can from that. You could try to find a company > > specialising in data recovery and pay them to try to get your data > > back. Or you might just have to accept that the data's gone and work > > on reconstructing it. > > Only thing that comes to my mind thats still tryable without involving > a data recover firm or engage a developer for an improved recovery > tool is: > > PhotoRec from testdisk package or some other data recovery tool that > looks for headers for known fileformats like I think foremost. > > It has some drawbacks: > > - AFAIK it has no means to glue back together fragmented files, so > these are likely gone or truncated > > - filenames are lost > > - directory structure is lost It won´t work for striped files either, so it may only help for rather small files depending on BTRFS RAID 0 stripe size. -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7