If you rum rm command accidentally and deleted important a file, recovery becomes critical under Linux and/or UNIX oses.
Since Linux is multiuser and multitasking operating system other users/process can overwrite deleted file disk space. So you need to take down system to single user mode.
First use wall (only the super-user can write on the terminals of users) command write a message to all users, then use init (process control initialization) command to take system to single user mode.
Procedure
Following are generic steps to recover text files.
First use wall command to tell user that system is going down in a single user mode:
# wallOutput:
System is going down to .... please save your work.
Press CTRL+D to send message.
Next use init 1 command to take system to a single user mode:
# init 1
Using grep (traditional UNIX way) to recover files
Use following grep syntax:
grep -b 'search-text' /dev/partition > file.txt
OR
grep -a -B[size before] -A[size after] 'text' /dev/[your_partition] > file.txt
Where,
- -i : Ignore case distinctions in both the PATTERN and the input files i.e. match both uppercase and lowercase character.
- -a : Process a binary file as if it were text
- -B Print number lines/size of leading context before matching lines.
- -A: Print number lines/size of trailing context after matching lines.
To recover text file starting with "nixCraft" word on /dev/sda1 you can try following command:
# grep -i -a -B10 -A100 'nixCraft' /dev/sda1 > file.txt
Next use vi to see file.txt. This method is ONLY useful if deleted file is text file. If you are using ext2 file system, try out recover command. .
See also:
- See Recover homepage for more information
Featured Articles:
- 20 Linux System Monitoring Tools Every SysAdmin Should Know
- 20 Linux Server Hardening Security Tips
- 10 Greatest Open Source Software Of 2009
- My 10 UNIX Command Line Mistakes
- Top 5 Email Client For Linux, Mac OS X, and Windows Users
- Top 20 OpenSSH Server Best Security Practices
- Top 10 Open Source Web-Based Project Management Software
- Top 5 Linux Video Editor Software
- Email this to a friend
- Download PDF version
- Printable version
- Comment RSS feed
- Last Updated: Dec/17/2006
{ 11 comments… read them below or add one }
please show the whole procedure slide by slide so that layman can understand better.
the files in /var directory have gone missing in our solaris server.is there any way we can recover it???????please help
sridhar,
There is no real undelete available (until and unless you go for 3rd party commercial software). Restore file from backup. If it is config file restore by copying 3rd system or reinstalling package.
Appreciate your post.
i have removed .xsd files now i want them back.can anyone help me to get my .xsd files.
Thanks in advance
http://www.cgsecurity.org/wiki/PhotoRec
PhotoRec is file data recovery software designed to recover lost files including video, documents and archives from Hard Disks and CDRom and lost pictures (thus, its ‘Photo Recovery’ name) from digital camera memory. PhotoRec ignores the filesystem and goes after the underlying data, so it will still work even if your media’s filesystem has been severely damaged or re-formatted.
PhotoRec is free, this open source multi-platform application is distributed under GNU Public License. PhotoRec is a companion program to TestDisk, an app for recovering lost partitions on a wide variety of filesystems and making non-bootable disks bootable again. You can download them from this link.
For more safety, PhotoRec uses read-only access to handle the drive or memory support you are about to recover lost data from. Important: As soon as a pic or file is accidentally deleted, or you discover any missing, do NOT save any more pics or files to that memory device or hard disk drive; otherwise you may overwrite your lost data. This means that even using PhotoRec, you must not choose to write the recovered files to the same partition they were stored on.
PhotoRec runs under
* DOS/Win9x
* Windows NT 4/2000/XP/2003/Vista
* Linux
* FreeBSD, NetBSD, OpenBSD
* Sun Solaris
* Mac OS X
and can be compiled on almost every Unix system.
Photorec ignores the filesystem, this way it works even if the filesystem is severely damaged.
It can recover lost files at least from
* FAT,
* NTFS,
* EXT2/EXT3 filesystem
* HFS+
ReiserFS includes some special optimizations centered around tails, a name for files and end portions of files that are smaller than a filesystem block. In order to increase performance, ReiserFS is able to store files inside the b*tree leaf nodes themselves, rather than storing the data somewhere else on the disk and pointing to it. Unfortunately, PhotoRec isn’t able to deal with this, it’s why it doesn’t work well with ReiserFS.
Thank you! It worked!
It is not very clear in the instructions, but “nixCraft” is not the name of the file, is something wrote in the beginning of the file…
Whew…that saved me some time. Very helpful, thank you!
even i am using
# rm -rf /export/home/john
is there any command to recover this folder again
Hi all,
I just had to recover a file from ext3 on Ubuntu, and used the utility ext3grep to do so.
It’s in the Ubuntu repositories, so install it before you need it:
sudo aptitude install ext3grep
And remember, if you are storing your backups encrypted, keep the password to the encrypted folder in a file SEPARATELY (not in the encrypted folder), so when you delete it, you can just restore it, rather than get that ’sinking feeling’…
I was lucky, ext3grep worked for me – I had to follow the manual recovery examples on the ext3grep homepage, the auto recovery didn’t do it for me.
Best of luck to you!
my initrd file is deleted and my pc is not boot so how can i recover..?
please tell me m waiting for ur reply..
plz tell me commands..
This saved my life. Got a very important source code file back, 100%. Would have taken me days to rewrite. Didn’t delete a file, but server/samba failed, and stored a file of size 0 on top of the file. Have seen it before. Thank you.