From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qa0-f49.google.com ([209.85.216.49]:63286 "EHLO mail-qa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753310Ab2FGD1E (ORCPT ); Wed, 6 Jun 2012 23:27:04 -0400 Received: by qabj40 with SMTP id j40so248078qab.1 for ; Wed, 06 Jun 2012 20:27:02 -0700 (PDT) Message-ID: <4FD01F85.9020405@gmail.com> Date: Wed, 06 Jun 2012 23:27:01 -0400 From: Maxim Mikheev MIME-Version: 1.0 To: Michael CC: Hugo Mills , Liu Bo , linux-btrfs@vger.kernel.org Subject: Re: Help with data recovering References: <4FCC9C63.7000605@gmail.com> <4FCC9CD5.2050309@gmx.net> <4FCC9F6C.5090305@gmail.com> <20120604114901.GA15986@carfax.org.uk> <4FCCA39C.8060409@gmail.com> <20120604121134.GB15986@carfax.org.uk> <4FCCA9E6.3030209@gmail.com> <20120604123431.GC15986@carfax.org.uk> <4FCCE125.7000004@gmail.com> <20120604170422.GD15986@carfax.org.uk> <20120604170936.GE15986@carfax.org.uk> <4FCCF882.5080500@gmail.com> <4FCF8485.4080802@gmail.com> In-Reply-To: <4FCF8485.4080802@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: Hi Everyone, Is it possible to extract specific file instead of downloading everything? Thanks On 06/06/2012 12:25 PM, Maxim Mikheev wrote: > Option -i was helpful. > Some date was restored. > > during restoring some files I got message "ret is -3". This files has > 0 size. > Can anyone tell me what is code "-3" mean. Is it recoverable? > > So basically data is on harddrives but not completely available. > the questions is: Is it possible to btrfs push to roll back on several > generations? > > Thanks > > On 06/04/2012 02:37 PM, Michael wrote: >> Below is what you used? So you have RAID 0 for data, RAID 1 for >> metadata. This doesn't help any, but a point of info. >> # Create a filesystem across four drives (metadata mirrored, data >> striped) >> mkfs.btrfs /dev/sdb /dev/sdc /dev/sdd /dev/sde >> >> >> Just to make sure I understand correctly: This FS with critical info >> used a non-production filesystem, in RAID 0(no redundancy), with no >> backups. >> >> Another option I found(and I am no authority on the subject) is to use >> btrfs.restore with -i >> -i: Ignore errors. Normally the restore tool exits immediately for any >> error. This option forces it to keep going if it can, usually this >> results in some missing data. >> Again, this can be destructive, and it would be very smart to make >> block level copies of everything. >> >> On Mon, Jun 4, 2012 at 1:03 PM, Maxim Mikheev wrote: >>> It was a RAID0 unfortunately. >>> >>> >>> On 06/04/2012 02:02 PM, Michael wrote: >>>> If he has it in a RAID 1, could he manually fail the bad disk and try >>>> it from there? Obviously this could be harmful, so a dd copy would be >>>> a VERY good idea(truthfully, that should have been the first thing >>>> that was done). >>>> Michael >>>> >>>> On Mon, Jun 4, 2012 at 12:09 PM, Hugo Mills >>>> wrote: >>>>> On Mon, Jun 04, 2012 at 06:04:22PM +0100, Hugo Mills wrote: >>>>>> I'm out of ideas. >>>>> ... but that's not to say that someone else may have some ideas. I >>>>> wouldn't get your hopes up too much, though. >>>>> >>>>>> 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. >>>>> Hugo. >>>>> >>>>> -- >>>>> === Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | >>>>> lug.org.uk === >>>>> PGP key: 515C238D from wwwkeys.eu.pgp.net or >>>>> http://www.carfax.org.uk >>>>> --- A linked list is still a binary tree. Just a very >>>>> unbalanced --- >>>>> one. -- dragon