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linux刪除的檔案如何恢復？

青灯夜游原創: 2020-04-20 16:12:2319211瀏覽

linux刪除的檔案如何恢復？以下這篇文章為大家介紹一下恢復Linux刪除檔案的方法。有一定的參考價值，有需要的朋友可以參考一下，希望對大家有幫助。

linux刪除的檔案如何恢復？

linux不像windows有個回收站，使用rm -rf *基本上檔案是找不回來的。

那麼問題來了：

對於linux下誤刪的文件，我們是否真的無法透過軟體進行恢復呢?

答案當然是否定的，對於誤刪的文件，我們還是能透過軟體恢復過來的。誤刪檔案還原可以分成兩種情況:

一種是刪除以後在行程存在刪除資訊
一種是刪除以後進程都找不到，只有借助工具還原。

接下來以範例分別解說下兩種不同的誤刪還原方式：

錯誤刪除檔案程式還在的情況:

這種一般是有活動的進程存在持續標準輸入或輸出，到時檔案被刪除後，進程PID依舊存在。這也是為什麼有些伺服器刪除一些檔案但是磁碟不釋放的原因。

打開一個終端機對一個測試檔案做cat追加操作：

[root@docking ~]# echo "This is DeleteFile test." > deletefile.txt
[root@docking ~]# ls
deletefile.txt
[root@docking ~]# cat >> deletefile.txt 
Add SomeLine into deletefile for fun.

打開另外一個終端機查看這個檔案可以清楚看到內容：

[root@docking ~]# ls
deletefile.txt
[root@docking ~]# cat deletefile.txt 
This is DeleteFile test.
Add SomeLine into deletefile for fun.

此時，刪除文件rm -f deletefile.txt

[root@docking ~]# rm -f deletefile.txt 
[root@docking ~]# ls
#命令查看这个目录，文件已经不存在了，那么现在我们将其恢复出来。

lsof查看刪除的檔案程式是否還存在。
如沒有安裝請自行yum install lsof或apt-get install lsof

1.類似這種情況，我們可以先lsof查看刪除的檔案是否還在

[root@docking ~]# lsof | grep deletefile
cat       21796          root    1w      REG              253,1        63     138860 /root/deletefile.txt (deleted)

2、恢復cp /proc/pid/fd/1 /指定目錄/檔案名稱

#進入進程目錄，一般是進入/proc/pid/fd/,針對當前情況：

[root@docking ~]# cd /proc/21796/fd
[root@docking fd]# ll
总用量 0
lrwx------ 1 root root 64 1月  18 22:21 0 -> /dev/pts/0
l-wx------ 1 root root 64 1月  18 22:21 1 -> /root/deletefile.txt (deleted)
lrwx------ 1 root root 64 1月  18 22:21 2 -> /dev/pts/0

恢復操作：

[root@docking fd]# cp 1 ~/deletefile.txt.backup
[root@docking fd]# cat ~/deletefile.txt.backup 
This is DeleteFile test.
Add SomeLine into deletefile for fun.

3、恢復完成。

誤刪除的檔案進程已經不存在，借助工具還原

#準備一些檔案目錄

#准备一份挂载的盘
mkdir backuptest
cd backuptest
mkdir deletetest
mkdir deletetest/innerfolder
echo "Delete a folder test." > deletetest/innerfolder/deletefile.txt 

echo "tcpdump:x:172:72::/:/sbin/nologin" > tmppasswd

最後準備的目錄結構如下：

taroballs@taroballs-PC:/media/taroballs/taroballs/backuptest$ cd ..
taroballs@taroballs-PC:/media/taroballs/taroballs$ tree backuptest/
backuptest/
├── deletetest
│   └── innerfolder
│       └── deletefile.txt
└── tmppasswd

2 directories, 2 files

現在開始刪除該目錄rm -rf backuptest/

taroballs@taroballs-PC:/media/taroballs/taroballs$ rm -rf backuptest/
taroballs@taroballs-PC:/media/taroballs/taroballs$  ls  -l
总用量 0

這種情況一般是沒有守護進行或後台程序對其持續輸入，所以刪除就真的刪除了。 lsof也看不到，故需要採用工具來恢復。

現在開始進行誤刪除檔案的復原。

我們採用的工具是extundelete第三方工具。復原步驟以及注意事項如下：

停止對目前分割區做任何操作，防止inode被覆寫。 inode被覆蓋基本上就告別恢復了。
誇張一點講，例如停止所在分區的服務，卸載目錄所在的設備，有必要的情況下都可以斷網。
透過dd指令對目前分割區進行備份，防止第三方軟體復原失敗導致資料遺失。
適合資料非常重要的情況，這裡是例子，所以就沒有備份，例如備份可以考慮如下方式：dd if=/path/filename of=/dev/vdc1
透過umount指令，對目前裝置分割區卸載。或fuser 指令umount /dev/vdb1
如果提示裝置busy，可以用fuser指令強制卸載：fuser -m -v -i -k ./
#下載第三方工具extundelete安裝，搜尋誤刪除的檔案還原

#extundelete工具安裝

extundelete下載位址： http://extundelete.sourceforge.net/

wget https://nchc.dl.sourceforge.net/project/extundelete/extundelete/0.2.4/extundelete-0.2.4.tar.bz2

解壓縮該檔案tar jxvf extundelete-0.2.4.tar.bz2

#若報這種錯誤

[root@docking ~]# tar jxvf extundelete-0.2.4.tar.bz2 
tar (child): bzip2：无法 exec: 没有那个文件或目录
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now

則使用yum -y install bzip2進行解決

[root@docking ~]# tar jxvf extundelete-0.2.4.tar.bz2 
extundelete-0.2.4/
extundelete-0.2.4/acinclude.m4
extundelete-0.2.4/missing
extundelete-0.2.4/autogen.sh
extundelete-0.2.4/aclocal.m4
extundelete-0.2.4/configure
extundelete-0.2.4/LICENSE
extundelete-0.2.4/README
...................................................

cd  extundelete-0.2.4
./configure

若這步驟報錯

[root@docking extundelete-0.2.4]# ./configure 
Configuring extundelete 0.2.4
configure: error: in `/root/extundelete-0.2.4&#39;:
configure: error: C++ compiler cannot create executables
See `config.log&#39; for more details

則使用yum -y install gcc-c 解決.

若執行上一個步驟仍然報錯，

[root@docking extundelete-0.2.4]# ./configure 
Configuring extundelete 0.2.4
configure: error: Can&#39;t find ext2fs library

則使用yum -y install e2fsprogs e2fsprogs-devel來解決。
#Ubuntu的解決方法為sudo apt-get install e2fslibs-dev e2fslibs-dev

不出意外的話到這裡應該configure能夠順利完成.

[root@docking extundelete-0.2.4]# ./configure 
Configuring extundelete 0.2.4
Writing generated files to disk
[root@docking extundelete-0.2.4]#

最後make然後 make install

[root@docking extundelete-0.2.4]# make
make -s all-recursive
Making all in src
extundelete.cc: 在函数‘ext2_ino_t find_inode(ext2_filsys, ext2_filsys, ext2_inode*, std::string, int)’中:
extundelete.cc:1272:29: 警告：在 {} 内将‘search_flags’从‘int’转换为较窄的类型‘ext2_ino_t {aka unsigned int}’ [-Wnarrowing]
    buf, match_name2, priv, 0};
                             ^
[root@docking extundelete-0.2.4]# make install
Making install in src
  /usr/bin/install -c extundelete &#39;/usr/local/bin&#39;

extundelete安裝完成.

##掃描錯誤刪除的檔案：

使用

df -lh查看掛載：

taroballs@taroballs-PC:~$ df -lh
文件系统        容量  已用  可用 已用% 挂载点
udev            1.9G     0  1.9G    0% /dev
tmpfs           387M  1.8M  385M    1% /run
/dev/sda2        92G   61G   26G   71% /
tmpfs           1.9G   49M  1.9G    3% /dev/shm
tmpfs           5.0M  4.0K  5.0M    1% /run/lock
tmpfs           1.9G     0  1.9G    0% /sys/fs/cgroup
/dev/sda3       104G   56G   44G   57% /home
tmpfs           387M   40K  387M    1% /run/user/1000
/dev/sda4        70G   20G   47G   30% /media/taroballs/d8423f8c-d687-4c03-a7c8-06a7fb57f96d
/dev/sdb1       6.8G  4.1G  2.8G   60% /media/taroballs/taroballs
/dev/sr0        4.0G  4.0G     0  100% /media/taroballs/2018-01-16-12-36-00-00
taroballs@taroballs-PC:~$ cd /media/taroballs/taroballs/
taroballs@taroballs-PC:/media/taroballs/taroballs$

可以看到，我們的目錄/media/taroballs/taroballs

掛載到/dev/sdb1這個檔案系統中.

umount我們的掛載碟

例如：

taroballs@taroballs-PC:~$ df -lh | grep /dev/sdb1
/dev/sdb1       6.8G  4.1G  2.8G   60% /media/taroballs/taroballs

umount這個目錄

taroballs@taroballs-PC:~$ umount /media/taroballs/taroballs
taroballs@taroballs-PC:~$ df -lh | grep /dev/sdb1
taroballs@taroballs-PC:~$ 
#记得删除一定要后umount哦，不然二次写入谁也帮不了你呢。

#透過inode節點復原

taroballs@taroballs-PC:~$ mkdir recovertest
taroballs@taroballs-PC:~$ cd recovertest/
taroballs@taroballs-PC:~/recovertest$

執行復原

extundelete /dev/sdb1 --inode 2

taroballs@taroballs-PC:/media/taroballs/taroballs$ sudo extundelete /dev/sdb1 --inode 2
NOTICE: Extended attributes are not restored.
Loading filesystem metadata ... 8 groups loaded.
Group: 0
Contents of inode 2:
 
.
.省略N行
 
File name                                       | Inode number | Deleted status
.                                                 2
..                                                2
deletetest                                        12             Deleted
tmppasswd                                            14             Deleted

透過掃描發現了我們刪除的資料夾，現在執行恢復操作。

（1）恢復單一檔案tmppasswd

taroballs@taroballs-PC:~/recovertest$  extundelete /dev/sdb1 --restore-file passwd   
NOTICE: Extended attributes are not restored.
Loading filesystem metadata ... 8 groups loaded.
Loading journal descriptors ... 46 descriptors loaded.
Successfully restored file tmppasswd

恢復檔案是放到了目前目錄RECOVERED_FILES。

查看恢復的檔案：

taroballs@taroballs-PC:~/recovertest$ cat tmppasswd 
tcpdump:x:172:72::/:/sbin/nologin

（2）恢復目錄deletetest

extundelete /dev/sdb1 --restore-directory  deletetest
NOTICE: Extended attributes are not restored.
Loading filesystem metadata ... 8 groups loaded.
Loading journal descriptors ... 46 descriptors loaded.
Searching for recoverable inodes in directory deletetest ... 
5 recoverable inodes found.
Looking through the directory structure for deleted files ...

（3）恢復所有

taroballs@taroballs-PC:~/recovertest$ extundelete /dev/sdb1 --restore-all
NOTICE: Extended attributes are not restored.
Loading filesystem metadata ... 8 groups loaded.
Loading journal descriptors ... 46 descriptors loaded.
Searching for recoverable inodes in directory / ... 
5 recoverable inodes found.
Looking through the directory structure for deleted files ... 
0 recoverable inodes still lost. 
taroballs@taroballs-PC:~/recovertest$ tree 
backuptest/
├── deletetest
│   └── innerfolder
│       └── deletefile.txt
└── tmppasswd
2 directories, 2 files

（4）恢復指定inode

taroballs@taroballs-PC:~/recovertest$ extundelete /dev/sdb1 --restore-inode 14
NOTICE: Extended attributes are not restored.
Loading filesystem metadata ... 8 groups loaded.
Loading journal descriptors ... 46 descriptors loaded.
taroballs@taroballs-PC:~/recovertest$ cat file.14 
tcpdump:x:172:72::/:/sbin/nologin
#注意恢复inode的时候，恢复 出来的文件名和之前不一样，需要单独进行改名。

最後附上

extundelete的用法:

$ extundelete --help
Usage: extundelete [options] [--] device-file
Options:
  --version, -[vV]       Print version and exit successfully.
  --help,                Print this help and exit successfully.
  --superblock           Print contents of superblock in addition to the rest.
                         If no action is specified then this option is implied.
  --journal              Show content of journal.
  --after dtime          Only process entries deleted on or after &#39;dtime&#39;.
  --before dtime         Only process entries deleted before &#39;dtime&#39;.Actions:
  --inode ino            Show info on inode &#39;ino&#39;.
  --block blk            Show info on block &#39;blk&#39;.
  --restore-inode ino[,ino,...]
                         Restore the file(s) with known inode number &#39;ino&#39;.
                         The restored files are created in ./RECOVERED_FILES                         with their inode number as extension (ie, file.12345).
  --restore-file &#39;path&#39;  Will restore file &#39;path&#39;. &#39;path&#39; is relative to root
                         of the partition and does not start with a &#39;/&#39;
                         The restored file is created in the current
                         directory as &#39;RECOVERED_FILES/path&#39;.
  --restore-files &#39;path&#39; Will restore files which are listed in the file &#39;path&#39;.
                         Each filename should be in the same format as an option
                         to --restore-file, and there should be one per line.
  --restore-directory &#39;path&#39;
                         Will restore directory &#39;path&#39;. &#39;path&#39; is relative to the
                         root directory of the file system.  The restored
                         directory is created in the output directory as &#39;path&#39;.
  --restore-all          Attempts to restore everything.
  -j journal             Reads an external journal from the named file.
  -b blocknumber         Uses the backup superblock at blocknumber when opening
                         the file system.
  -B blocksize           Uses blocksize as the block size when opening the file
                         system.  The number should be the number of bytes.
  --log 0                Make the program silent.
  --log filename         Logs all messages to filename.--log D1=0,D2=filename   Custom control of log messages with comma-separated
   Examples below:       list of options.  Dn must be one of info, warn, or   --log info,error      error.  Omission of the &#39;=name&#39; results in messages   --log warn=0          with the specified level to be logged to the console.
   --log error=filename  If the parameter is &#39;=0&#39;, logging for the specified
                         level will be turned off.  If the parameter is
                         &#39;=filename&#39;, messages with that level will be written
                         to filename.
   -o directory          Save the recovered files to the named directory.
                         The restored files are created in a directory
                         named &#39;RECOVERED_FILES/&#39; by default.

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