undelete files on ext4

Question

My mother has placed some important files on her /tmp per accident. Now, of course, they are gone.

This happened yesterday (2 boots of the machine since)

I want to try to undelete the files. They were on /tmp, which was on the same partition as the rest of / , so I need a tool that runs on a mounted system (or maybe I could use a livecd ...)

Right now, I am trying testdisk on a systemrescuecd that I just downloaded. I can get some files from /tmp, but not all. (is it the right tool ? What exactly are those "red" files ? are only some of them recoverable ?)

Solution 1

You can also use extundelete

First unmount (umount) the file system where the files have been deleted.
Then read the chapter What to do if you've deleted a file.

You can install extundelete from classic Ubuntu repository:

sudo apt-get install extundelete

Or better, you can download the latest version and compile it:

cd ~/Download
tar -xf extundelete-*.*.*-.tar.bz2  #Replace *.*.* by the version
cd      extundelete-*.*.*
sudo apt-get install e2fslibs-dev   #Required for compilation
./configure
make
sudo make install
extundelete --version               #Should be your *.*.* version

Example of usage: restore all deleted files from directory Images into new created directory restore

sudo extundelete --restore-directory Images/ -o restore /dev/sda3

Bad news if you see your file XXXX within the following format:

Unable to restore inode NNN (Images/XXXX): Space has been reallocated.

See all restored files (look for your file):

find restore -name '*'

Backup your file(s) and remove this temporary directory restore

cp restore/Images/XXXX MY_BACKUP_DIRECTORY
sudo rm -rf restore  

Solution 2

Data recovery, especially on EXT file systems, should be attempted from a live CD or other system that isn't depending on the partition you're undeleting from. Getting the disk unmounted or re-mounted as read only helps a great deal in the recovery effort.

Most of the time I try to create an image of the partition or disk using dd or a similar tool, so that I'm not working on the disk itself:

dd if=/dev/sd[xx] of=/media/backup_drive/recovery.img

Once you have your image, you can use a tool like ext3grep to try and find the files you're looking for. There are lots of different switches that you can try, but this might be a good start:

ext3grep --restore-file 'tmp/moms-file.txt' recovery.img

The ext3grep utility also provides several different ways to search through the file system if you don't know the name of the file. Check ext3grep --help for the various methods of searching.

Solution 3

I prefered to use ext4magic as :

sudo ext4magic  /dev/sdc3 -r -f $USERl/Documents/ -d /tmp/local/tmp/

Note you have to resolv symlink by your own

References:

http://ext4magic.sourceforge.net/howto_en.html

http://sourceforge.net/projects/ext4magic/

http://rzr.online.fr/q/recover

Solution 4

AnalyzeEXT

Parse data blocks for EXT directory data.

Detailed documentation on EXT4 can be found here:

• https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout
• https://digital-forensics.sans.org/blog/tags/ext4

Download the perl script with

git clone https://github.com/halpomeranz/analyzeEXT

No guarantee but may be able to reconstruct deleted filesystems.

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Comments

[0xC0000022L]

The best solution is probably a backup and the next best solution for someone who is technically less apt than you perhaps btrfs with frequent snapshots. Packages like restic, rdiff-backup, duplicity or backintime-qt may also be of interest. None of this is going to help you in retrospect, but perhaps this comment helps future visitors.

[Vorac]

For me extundelete segments, while testdisk whips out a list of differences. Now to see if it can get the files back.

[saji89]

It would be nice, if you could add the exact steps?

[prathvi]

@saji89 Added a sample usage - also fixed to link to the right utility!

[josinalvo]

nice. now ... does it work with ext4 ?

[prathvi]

@josinalvo I was working with an EXT4 volume when I tried it, and it did work; it didn't find the files I was looking for, but I think I had missed the window of opportunity.

[Twifty]

This answer has literally just saved my job. Thankyou.

[wjandrea]

What is this tool exactly? How do you use it? I've read the repo description and the help message in the script, but there's not much detail.

[abu_bua]

Took a look at the perl script; the cli help doesn't match with the script!

[jouell]

More details are here. I stumbled up on it - never used it! youtube.com/watch?v=6pzm6909IvY

[wjandrea]

@jouell I've watched 2:30 of the video and he hasn't mentioned the script yet. Could you edit your answer to add a brief summary?

[Onza]

I get segmentation fault, core dumped.