Daten wiederherstellen mit ext3grep: Unterschied zwischen den Versionen

Version vom 14. November 2009, 14:51 Uhr

Das übliche Problem: Ein oder mehrere Dateien und Verzeichnisse auf einem ext3 Dateisystem wurden versehentlich gelöscht. Unter Linux gibt es für diesen Fall ein Tool namens ext3grep, das verwendet man so:

Betroffene Partition unmounten:

~ # umount /dev/mapper/via_bgeedgfhid3
umount: /media: device is busy.
~ # fuser /dev/mapper/via_bgeedgfhid3
~ # lsof /dev/mapper/via_bgeedgfhid3
COMMAND   PID   USER   FD   TYPE DEVICE SIZE/OFF     NODE NAME
smbd     7354 andor2  cwd    DIR  253,3     4096 50888705 /media/
~ # /etc/init.d/samba stop
~ # umount /dev/mapper/via_bgeedgfhid3

In der Partition nach dem verlorenen Verzeichnis oder einer Datei suchen:

~ # ext3grep --search tolledatei /dev/mapper/via_bgeedgfhid3
Running ext3grep version 0.10.1
Number of groups: 3488
Minimum / maximum journal block: 1545 / 35886
Loading journal descriptors... sorting... done
The oldest inode block that is still in the journal, appears to be from 1257372505 = Wed Nov  4 23:08:25 2009
Journal transaction 3424402 wraps around, some data blocks might have been lost of this transaction.
Number of descriptors in journal: 29754; min / max sequence numbers: 3423360 / 3426366
Blocks containing "tolledatei": 20992 (allocated) 21310 (allocated) 24267 (allocated) 24275 (allocated) 
24306 (allocated) 24326 (allocated) 24332 (allocated) 24345 (allocated) 24359 (allocated) 24365 (allocated) 
24377 (allocated) 24397 (allocated) 24403 (allocated) 24416 (allocated) 24430 (allocated) 24436 (allocated) 
24449 (allocated) 24455 (allocated) 24464 (allocated) 24495 (allocated) 24543 (allocated) 24557 (allocated) 
24603 (allocated) 24622 (allocated) 24665 (allocated) 24681 (allocated) 24727 (allocated) 24742 (allocated) 
24788 (allocated) 24803 (allocated) 24850 (allocated) 24875 (allocated) 24883 (allocated) 25277 (allocated) 
25974 (allocated) 26024 (allocated) 26037 (allocated)

Die Blöcke kann man sich jetzt alle anschauen um den wiederherzustellenden inode zu finden:

~ # ext3grep /dev/mapper/via_bgeedgfhid3 --ls --block
Running ext3grep version 0.10.1
Number of groups: 3488
Loading group metadata... done
Minimum / maximum journal block: 1545 / 35886
Loading journal descriptors... sorting... done
The oldest inode block that is still in the journal, appears to be from 1257372505 = Wed Nov  4 23:08:25 2009
Journal transaction 3424402 wraps around, some data blocks might have been lost of this transaction.
Number of descriptors in journal: 29754; min / max sequence numbers: 3423360 / 3426366
Group: 0
Block 24681 is a directory. The block is a Journal block
          .-- File type in dir_entry (r=regular file, d=directory, l=symlink)
          |          .-- D: Deleted ; R: Reallocated
Indx Next |  Inode   | Deletion time                        Mode        File name
==========+==========+----------------data-from-inode------+-----------+=========
   0    1 d28902421                                         drwxrwxr-x  .
   1    2 d28902420                                         drwxrwxr-x  ..
   2    3 r42893329  D 1258196891 Sat Nov 14 12:08:11 2009  rrw-rw-r--  tolledatei.test

Ist der inode gefunden, kann man ihn so wiederherstellen:

~ # ext3grep /dev/mapper/via_bgeedgfhid3 --restore-inode 42893329
Running ext3grep version 0.10.1
Number of groups: 3488
Minimum / maximum journal block: 1545 / 35886
Loading journal descriptors... sorting... done
The oldest inode block that is still in the journal, appears to be from 1257372505 = Wed Nov  4 23:08:25 2009
Journal transaction 3424402 wraps around, some data blocks might have been lost of this transaction.
Number of descriptors in journal: 29754; min / max sequence numbers: 3423360 / 3426366
Restoring inode.42893329

Dieser ist dann im folgenden Verzeichnis zu finden:

~ # ll RESTORED_FILES/
total 29M
-rw-r--r-- 1 root root  29M Nov 12 22:37 inode.42893329