Reiser4 file recovery

Reiser4 file recovery

[Yiannis Mavroukakis]

Hello :-)

I had an LVM setup of three disks, and one of them went belly 
up..Obvious thought is, use some
distro like R.I.P to reduce the volume to two disks and try and salvage 
what I could ..unfortunately reiser4 fsck could not find a superblock 
(surprise surprise the disk that died had it) nor could it build the FS 
because it cannot find the metadata..Under normal circumstances, I would 
not bother but my wife's mp3's are in those disks and she will have my 
head if I don't figure out some way to restore them :) Any suggestions?

Y.

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Re: Reiser4 file recovery

[michael chang]

On 10/10/05, Yiannis Mavroukakis <jander@darthvader.us> wrote:
> Hello :-)
>
> I had an LVM setup of three disks, and one of them went belly
> up..Obvious thought is, use some
> distro like R.I.P to reduce the volume to two disks and try and salvage
> what I could ..unfortunately reiser4 fsck could not find a superblock
> (surprise surprise the disk that died had it) nor could it build the FS
> because it cannot find the metadata..Under normal circumstances, I would
> not bother but my wife's mp3's are in those disks and she will have my
> head if I don't figure out some way to restore them :) Any suggestions?

Maybe you want to use RAID 5 or something instead of LVM, because of
parity, in the future.

I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
floppy or CD-ROM in DOS (the program makes images for you in Windows,
if you have a working partition, or you can get images from the site
IIRC once you've bought a copy) and see how much is recovered
(assuming it's just bad sectors or something).  Re-add it to the LVM,
recover to a seperate media, and then convert the whole thing to a
RAID (maybe via tar?).  I know it's not a free solution, but data
recovery is nearly impossible w/o paying in one way, shape, or form. 
It's easier to have backups.

--
~Mike
 - Just my two cents
 - No man is an island, and no man is unable.

Re: Reiser4 file recovery

[Christian Iversen]

On Monday 10 October 2005 17:06, michael chang wrote:
> On 10/10/05, Yiannis Mavroukakis <jander@darthvader.us> wrote:
> > Hello :-)
> >
> > I had an LVM setup of three disks, and one of them went belly
> > up..Obvious thought is, use some
> > distro like R.I.P to reduce the volume to two disks and try and salvage
> > what I could ..unfortunately reiser4 fsck could not find a superblock
> > (surprise surprise the disk that died had it) nor could it build the FS
> > because it cannot find the metadata..Under normal circumstances, I would
> > not bother but my wife's mp3's are in those disks and she will have my
> > head if I don't figure out some way to restore them :) Any suggestions?
>
> Maybe you want to use RAID 5 or something instead of LVM, because of
> parity, in the future.
>
> I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
> floppy or CD-ROM in DOS (the program makes images for you in Windows,
> if you have a working partition, or you can get images from the site
> IIRC once you've bought a copy) and see how much is recovered
> (assuming it's just bad sectors or something).  Re-add it to the LVM,
> recover to a seperate media, and then convert the whole thing to a
> RAID (maybe via tar?).  I know it's not a free solution, but data
> recovery is nearly impossible w/o paying in one way, shape, or form.
> It's easier to have backups.

As usually, Gibson "Research" is skimpy on details, so I'm not entirely sure 
if spinrite is anything more than a disk imager. If not, just use the free 
(gratis && libre) dd_rescue program instead. It will save you $50.

-- 
Regards,
Christian Iversen

Re: Reiser4 file recovery

[Yiannis Mavroukakis]

Christian Iversen wrote:

>On Monday 10 October 2005 17:06, michael chang wrote:
>  
>
>>On 10/10/05, Yiannis Mavroukakis <jander@darthvader.us> wrote:
>>    
>>
>>>Hello :-)
>>>
>>>I had an LVM setup of three disks, and one of them went belly
>>>up..Obvious thought is, use some
>>>distro like R.I.P to reduce the volume to two disks and try and salvage
>>>what I could ..unfortunately reiser4 fsck could not find a superblock
>>>(surprise surprise the disk that died had it) nor could it build the FS
>>>because it cannot find the metadata..Under normal circumstances, I would
>>>not bother but my wife's mp3's are in those disks and she will have my
>>>head if I don't figure out some way to restore them :) Any suggestions?
>>>      
>>>
>>Maybe you want to use RAID 5 or something instead of LVM, because of
>>parity, in the future.
>>
>>I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
>>floppy or CD-ROM in DOS (the program makes images for you in Windows,
>>if you have a working partition, or you can get images from the site
>>IIRC once you've bought a copy) and see how much is recovered
>>(assuming it's just bad sectors or something).  Re-add it to the LVM,
>>recover to a seperate media, and then convert the whole thing to a
>>RAID (maybe via tar?).  I know it's not a free solution, but data
>>recovery is nearly impossible w/o paying in one way, shape, or form.
>>It's easier to have backups.
>>    
>>
>
>As usually, Gibson "Research" is skimpy on details, so I'm not entirely sure 
>if spinrite is anything more than a disk imager. If not, just use the free 
>(gratis && libre) dd_rescue program instead. It will save you $50.
>
>  
>
Thanks for the suggestions guys...however I should have clarified that I 
no longer have the dead disk (long story...) so I am kind of stuck with 
what I have...Am I stuffed ?

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Re: Reiser4 file recovery

[Christian Iversen]

On Monday 10 October 2005 17:19, Yiannis Mavroukakis wrote:
> Christian Iversen wrote:
> >On Monday 10 October 2005 17:06, michael chang wrote:
> >>On 10/10/05, Yiannis Mavroukakis <jander@darthvader.us> wrote:
> >>>Hello :-)
> >>>
> >>>I had an LVM setup of three disks, and one of them went belly
> >>>up..Obvious thought is, use some
> >>>distro like R.I.P to reduce the volume to two disks and try and salvage
> >>>what I could ..unfortunately reiser4 fsck could not find a superblock
> >>>(surprise surprise the disk that died had it) nor could it build the FS
> >>>because it cannot find the metadata..Under normal circumstances, I would
> >>>not bother but my wife's mp3's are in those disks and she will have my
> >>>head if I don't figure out some way to restore them :) Any suggestions?
> >>
> >>Maybe you want to use RAID 5 or something instead of LVM, because of
> >>parity, in the future.
> >>
> >>I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
> >>floppy or CD-ROM in DOS (the program makes images for you in Windows,
> >>if you have a working partition, or you can get images from the site
> >>IIRC once you've bought a copy) and see how much is recovered
> >>(assuming it's just bad sectors or something).  Re-add it to the LVM,
> >>recover to a seperate media, and then convert the whole thing to a
> >>RAID (maybe via tar?).  I know it's not a free solution, but data
> >>recovery is nearly impossible w/o paying in one way, shape, or form.
> >>It's easier to have backups.
> >
> >As usually, Gibson "Research" is skimpy on details, so I'm not entirely
> > sure if spinrite is anything more than a disk imager. If not, just use
> > the free (gratis && libre) dd_rescue program instead. It will save you
> > $50.
>
> Thanks for the suggestions guys...however I should have clarified that I
> no longer have the dead disk (long story...) so I am kind of stuck with
> what I have...Am I stuffed ?

In a word, mu. 

Since you lost all the metadata, recovery of the filesystem structure is 
impossible. What you can still do, however, is attempt automated recovery 
using file "magic"-signatures. One very good program that does exactly this, 
is Jonas Jensen's Magic Rescue:

http://jbj.rapanden.dk/magicrescue/

This has many "recipes" for finding files. The included ones can search for 
png, jpeg, zip and several others. I know there's a recipe for MP3s as well.

Let us know how it works out.

-- 
Regards,
Christian Iversen

Re: Reiser4 file recovery

[Gregory Maxwell]

On 10/10/05, Christian Iversen <chrivers@iversen-net.dk> wrote:

> > I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
> > floppy or CD-ROM in DOS (the program makes images for you in Windows,
> > if you have a working partition, or you can get images from the site
> > IIRC once you've bought a copy) and see how much is recovered
> > (assuming it's just bad sectors or something).  Re-add it to the LVM,
> > recover to a seperate media, and then convert the whole thing to a
> > RAID (maybe via tar?).  I know it's not a free solution, but data
> > recovery is nearly impossible w/o paying in one way, shape, or form.
> > It's easier to have backups.
>
> As usually, Gibson "Research" is skimpy on details, so I'm not entirely sure
> if spinrite is anything more than a disk imager. If not, just use the free
> (gratis && libre) dd_rescue program instead. It will save you $50.

A decade ago spinright would put the disk into a low level mode where
it could read the ADC output and complete raw sectors... then it
performed something like PRML to recover the data. It was a miracle
worker. Back then, between that and a huge box of spare drives to swap
parts from I was able to recover almost all any dead drive that
crossed my desk.

No clue what spinrite does today, as I doubt that sort of low level
access is still possible, and even if it is, drives have become smart
enough to do a lot of that on their own.

Re: Reiser4 file recovery

[michael chang]

On 10/10/05, Gregory Maxwell <gmaxwell@gmail.com> wrote:
> On 10/10/05, Christian Iversen <chrivers@iversen-net.dk> wrote:
>
> > > I suggest you run Spinrite (grc.com, ~$50 IIRC) on the bad disk from a
> > > floppy or CD-ROM in DOS (the program makes images for you in Windows,
> > > if you have a working partition, or you can get images from the site
> > > IIRC once you've bought a copy) and see how much is recovered
> > > (assuming it's just bad sectors or something).  Re-add it to the LVM,
> > > recover to a seperate media, and then convert the whole thing to a
> > > RAID (maybe via tar?).  I know it's not a free solution, but data
> > > recovery is nearly impossible w/o paying in one way, shape, or form.
> > > It's easier to have backups.
> >
> > As usually, Gibson "Research" is skimpy on details, so I'm not entirely sure
> > if spinrite is anything more than a disk imager. If not, just use the free
> > (gratis && libre) dd_rescue program instead. It will save you $50.
>
> A decade ago spinright would put the disk into a low level mode where
> it could read the ADC output and complete raw sectors... then it
> performed something like PRML to recover the data. It was a miracle
> worker. Back then, between that and a huge box of spare drives to swap
> parts from I was able to recover almost all any dead drive that
> crossed my desk.
>
> No clue what spinrite does today, as I doubt that sort of low level
> access is still possible, and even if it is, drives have become smart
> enough to do a lot of that on their own.
>

I believe it still does that, and does so from a FreeDOS image which
you can put on a floppy, although it still runs from any DOS
installation also.  And it won't balk if you have a non-FAT drive,
it's been now designed to read all drive types (although I'd presume
that any FAT-specific recovery techniques wouldn't work on a non-FAT
drive).

IIRC, It also rereads and rewrites the drive in a maintanance mode to
ensure the data is 'refreshed' and doesn't die out as fast (if you
take a floppy, copy the data off, format, and rewrite the data, I've
noticed that the floppy seems to 'last longer' than if I just leave
data on it... so I'd presume similar applies also to hard disks).  The
only exception is the large amount of wear and tear put on the drive
head -- it's similar to that you would get when defragmenting a hard
disk.

--
~Mike
 - Just my two cents
 - No man is an island, and no man is unable.

Re: Reiser4 file recovery

[Sander]

Yiannis Mavroukakis wrote (ao):
> Thanks for the suggestions guys...however I should have clarified that
> I no longer have the dead disk (long story...)

FWIW, I'm interested in the story if you don't mind :-)

> so I am kind of stuck with what I have...Am I stuffed ?

You just lost one-third of your data, right?

-- 
Humilis IT Services and Solutions
http://www.humilis.net

Re: Reiser4 file recovery

[Matt Stegman]

On Mon, 10 Oct 2005, Christian Iversen wrote:
> Since you lost all the metadata, recovery of the filesystem structure is
> impossible. What you can still do, however, is attempt automated recovery
> using file "magic"-signatures. One very good program that does exactly this,
> is Jonas Jensen's Magic Rescue:
>
> http://jbj.rapanden.dk/magicrescue/
>
> This has many "recipes" for finding files. The included ones can search for
> png, jpeg, zip and several others. I know there's a recipe for MP3s as well.
>
> Let us know how it works out.

Just hope and pray your files aren't fragmented at all.  If they are, then
you NEED the metadata to know which fragments belong to which files (and
with Reiser's tail packing, file tails are located in tree nodes [I think]
which would be even harder to reconstruct).

In short, never throw away data if you want to have a chance of recovery.
If you can get that first disk back, do so before trying anything.

-- 
Matt Stegman

Re: Reiser4 file recovery

[michael chang]

On 10/10/05, Sander <sander@humilis.net> wrote:
> Yiannis Mavroukakis wrote (ao):
> > Thanks for the suggestions guys...however I should have clarified that
> > I no longer have the dead disk (long story...)
>
> FWIW, I'm interested in the story if you don't mind :-)

Ditto.

> > so I am kind of stuck with what I have...Am I stuffed ?
>
> You just lost one-third of your data, right?

Depends if all the MP3s were on that 1/3rd of the data that was lost.
If so, then yes, you are really badly stuffed.

--
~Mike
 - Just my two cents
 - No man is an island, and no man is unable.

Re: Reiser4 file recovery

[Yiannis Mavroukakis]

michael chang wrote:

>On 10/10/05, Sander <sander@humilis.net> wrote:
>  
>
>>Yiannis Mavroukakis wrote (ao):
>>    
>>
>>>Thanks for the suggestions guys...however I should have clarified that
>>>I no longer have the dead disk (long story...)
>>>      
>>>
>>FWIW, I'm interested in the story if you don't mind :-)
>>    
>>
>
>Ditto.
>
>  
>
>>>so I am kind of stuck with what I have...Am I stuffed ?
>>>      
>>>
>>You just lost one-third of your data, right?
>>    
>>
>
>Depends if all the MP3s were on that 1/3rd of the data that was lost.
>If so, then yes, you are really badly stuffed.
>
>n island, and no man is unable.
>  
>
I am hoping they are on the other two..we'll see tomorrow..
as for the how..it involves me cleaning the server in the balcony, spray
dusting a drive *over*
the balcony and jumping out of my skin when a friend tapped me on the
shoulder (thought I was alone in the flat)..
Drive vs Gravity 0 - 1