大家都知道Linux中，删除了的文件想恢复很难！而且不同文件系统下恢复的命令和工具可能还不一样。下面说下用debugfs，Linux中自带的命令，在ext3文件系统上恢复被删除文件的一次尝试.

    
[root]# mkdir /root/test                 //-->建测试文件夹
[root]# cd /root/test                    //-->进入该目录下
[root]# touch test.txt                   //-->建测试文件名
[root]# cat /proc/meminfo >> test.txt    //-->往测试文件写
[root]# cat test.txt
MemTotal:     16432172 kB
MemFree:       7577528 kB
Buffers:        896832 kB
Cached:        5724212 kB
SwapCached:          0 kB
Active:        2737104 kB
Inactive:      4246932 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:     16432172 kB
LowFree:       7577528 kB
SwapTotal:    16777208 kB
SwapFree:     16777208 kB
Dirty:            1944 kB
Writeback:           0 kB
AnonPages:      362976 kB
Mapped:         179000 kB
Slab:          1756168 kB
PageTables:       9432 kB
NFS_Unstable:        0 kB
Bounce:              0 kB
CommitLimit:  24993292 kB
Committed_AS:  1469296 kB
VmallocTotal: 34359738367 kB
VmallocUsed:    291068 kB
VmallocChunk: 34359447031 kB
HugePages_Total:     0
HugePages_Free:      0
HugePages_Rsvd:      0
Hugepagesize:     2048 kB
[root]# rm test.txt                            //-->删除此测试文件
[root]# ls -lart                               //-->查看是否删除
total 12
drwxr-x--- 6 root root 4096 Aug  6 09:51 ..
drwxr-xr-x 2 root root 4096 Aug  6 09:52 .

[root]# mount -r -n /dev/mapper/vg00-lvol1 /  //-->重新以只读的方式挂载，防止别的进程用

[root]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/rootVG-root
                       83G  7.4G   72G  10% /
/dev/mapper/rootVG-tmp
                      3.9G  137M  3.6G   4% /tmp
/dev/mapper/rootVG-var
                       31G  5.0G   24G  18% /var
/dev/cciss/c0d0p1     145M   26M  111M  19% /boot
/dev/mapper/vgglobal-lvol2
                       27G  291M   25G   2% /home
/dev/mapper/vgglobal-lvol1
                      105G  7.3G   93G   8% /d/oss/global
[root]# df -T
Filesystem    Type   1K-blocks      Used Available Use% Mounted on
/dev/mapper/rootVG-root
              ext3    86623180   7696528  74455460  10% /
/dev/mapper/rootVG-tmp
              ext3     4062912    139456   3713744   4% /tmp
/dev/mapper/rootVG-var
              ext3    31741856   5222564  24880892  18% /var
/dev/cciss/c0d0p1
              ext3      147764     26611    113524  19% /boot
/dev/mapper/vgglobal-lvol2
              ext3    27447508    297580  25755652   2% /home
/dev/mapper/vgglobal-lvol1
              ext3   109806464   7579200  96649332   8% /d/oss/global
[root]# debugfs                            //-->使用该命令
debugfs 1.39 (29-May-2006)
debugfs:  open /dev/mapper/rootVG-root     //-->打开文件系统
debugfs:  ls -d /root/test                 //-->查看被删文件
 16269861  (12) .  16269793  (4084) ..   <16269863> (4072) test.txt
debugfs:  logdump -i  <16269861>           //-->查看节点所在的块 
Inode 16269861 is at group 497, block 16285700, offset 512
Journal starts at block 6182, transaction 1128695
  FS block 16285700 logged at sequence 1128698, journal block 6330
    (inode block for inode 16269861):
    Inode: 16269861   Type: bad type        Mode:  0000   Flags: 0x0   Generation: 0
    User:     0   Group:     0   Size: 0
    File ACL: 0    Directory ACL: 0
    Links: 0   Blockcount: 0
    Fragment:  Address: 0    Number: 0    Size: 0
    ctime: 0x00000000 -- Thu Jan  1 07:00:00 1970
    atime: 0x00000000 -- Thu Jan  1 07:00:00 1970
    mtime: 0x00000000 -- Thu Jan  1 07:00:00 1970
    Blocks:
  FS block 16285700 logged at sequence 1128707, journal block 6860
    (inode block for inode 16269861):
    Inode: 16269861   Type: directory        Mode:  0755   Flags: 0x0   Generation: 285284165
    User:     0   Group:     0   Size: 4096
    File ACL: 0    Directory ACL: 0
    Links: 2   Blockcount: 8
    Fragment:  Address: 0    Number: 0    Size: 0
    ctime: 0x53e18a66 -- Wed Aug  6 09:52:38 2014
    atime: 0x53e18a44 -- Wed Aug  6 09:52:04 2014
    mtime: 0x53e18a66 -- Wed Aug  6 09:52:38 2014
    Blocks:  (0+1): 16312328
Found sequence 1127169 (not 1128751) at block 9518: end of journal
debugfs:  quit  //-->退出后，执行dd命令，count设置为1，skip为刚才查看的值，将其放在/tmp目录。
[root]# dd if=/dev/mapper/rootVG-root of=/tmp/test.txt.bak bs=4096 count=1 skip=16312328
1+0 records in
1+0 records out
4096 bytes (4.1 kB) copied, 4.1e-05 seconds, 99.9 MB/s
[root]# cat /tmp/test.txt     //-->检查内容，和原先的一致！

MemTotal:     16432172 kB
MemFree:       7577528 kB
Buffers:        896832 kB
Cached:        5724212 kB
SwapCached:          0 kB
Active:        2737104 kB
Inactive:      4246932 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:     16432172 kB
LowFree:       7577528 kB
SwapTotal:    16777208 kB
SwapFree:     16777208 kB
Dirty:            1944 kB
Writeback:           0 kB
AnonPages:      362976 kB
Mapped:         179000 kB
Slab:          1756168 kB
PageTables:       9432 kB
NFS_Unstable:        0 kB
Bounce:              0 kB
CommitLimit:  24993292 kB
Committed_AS:  1469296 kB
VmallocTotal: 34359738367 kB
VmallocUsed:    291068 kB
VmallocChunk: 34359447031 kB
HugePages_Total:     0
HugePages_Free:      0
HugePages_Rsvd:      0
Hugepagesize:     2048 kB