Re: Help with data recovering

[Maxim Mikheev <mikhmv@gmail.com>]

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<mikhmv@gmail.com>  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<hugo@carfax.org.uk>    
>>>> 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