Recovery of fast-erased DVD-RW

Using TestDisk to undelete files
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Bernecker
Posts: 3
Joined: 02 May 2016, 18:41

Recovery of fast-erased DVD-RW

#1 Post by Bernecker »

Hi Forum,

according to cgsecurity http://www.cgsecurity.org/wiki/CDRW#Rec ... nked_CD-RW it is possible to recover data from quick-erased DVDs with a linux system.

So I downloaded latest AltLinux, booted it via USB Stick, mounted the session as described at above link.
But then I am completely stalled. Neither testdisk nor photorec have the mounted thingy in the disk list, so I cannot start recovery from there.

Can someone explain why the mount?
And how to go on after the mount?

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cgrenier
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Joined: 18 Feb 2012, 15:08
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Re: Recovery of fast-erased DVD-RW

#2 Post by cgrenier »

Use "mount" to find the device and run "photorec /dev/sr0" (replace /dev/sr0 by the correct device).
Note that it doesn't work with all readers/writers

Bernecker
Posts: 3
Joined: 02 May 2016, 18:41

Re: Recovery of fast-erased DVD-RW

#3 Post by Bernecker »

Thanks cgrenier for the hints!
I am sadly a noob with linux, and couldnt start the recovery of fast-erased DVD-RW. Here is what happens using latest ALTLinux:

* I found out that /dev/sr0 is my DVD-recorder via

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# dmesg | egrep -i --color 'cdrom|dvd|cd/rw|writer'
* when I insert a "proper" DVD-RW (e.g. containing the sources of windows or ms office) then

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photorec /dev/sr0
would work well, i.e. it shows the DVD-RW on the intial screen.

* when I insert one of the DVD-RWs I want to recover then

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photorec /dev/sr0
does not work, it's output is:
"unable to open file or device /dev/sr0: no medium found"
* then I tried to mount the DVD-RW as follows:

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mkdir /home/cd

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mount /dev/sr0 /home/cd -t iso9660
which outputs:
"wrong fs type, bad option, bad superblock on /dev/sr0, missing codepage or helper program, or other error"
. Further info via

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dmesg | tail
:
Unable to identify CD-ROM format
Same result when I try

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-t udf
in the mount command.

Any ideas how I can make the DVDs accessible to photorec?

Bernecker
Posts: 3
Joined: 02 May 2016, 18:41

Re: Recovery of fast-erased DVD-RW

#4 Post by Bernecker »

Update:

I used an external USB DVD-ROM drive, and photorec now sees the disk when started via

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photorec /dev/sr0
.

One disk I tried before was not successful, photorec finished recovery after 2 seconds, not sure why this happened. Will investigate later.
I just run a recovery of another DVD-RW disk and this seems to work nicely in pass 1.

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