1) File system must be unmounted, you cannot repair it while it is running. Take system down to runlevel one (make sure you run all command as root user):
# init 1
2)Unmount file system, for example if it is /home (/dev/sda3) file system then type command:
# umount /home
OR
# umount /dev/sda3
3) Now run fsck on the partition:
# fsck /dev/sda3
However be sure to specify the file system type using -t option. Recenly one of our sys admin run the command on ext3 file system w/o specifying file system. Result was more corruption as fsck by default assumes ext2 file system.
# fsck -t ext3 /dev/sda3
OR
# fsck.ext3 /dev/sda3
Tip if you don't know your file system type then typing mount command will display file system type.
fsck will check the file system and ask which problems should be fixed or corrected. If you don't wanna type y every time then you can use pass -y option to fsck.
# fsck -y /dev/sda3
Please not if any files are recovered then they are placed in /home/lost+found directory by fsck command.
4) Once fsck finished, remount the file system:
# mount /home
5) Go to multiuser mode
# init 3
Read man page of fsck for more information. Make sure you replace /dev/sda3 with your actual device name.
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{ 20 comments… read them below or add one }
simple and effective :) good pice of work
can I try same commands on HP/UX?
Commands are same but syntax changes.
To repair HFS file system (/home)
umount /home
fsck –F hfs /dev/vg00/lvo1
mount /home
To repair JFS file system (/home)
umount /home
fsck –F vxfs /dev/vg00/lvo14
mount /home
Replace /dev/XXX/YYY with actual device file.
To repair a file system in HPUX
# fsck -F vxfs -y -o full /dev/vg##/lvol#
-or-
# fsck -F vxfs -o full -y /mount_pt
Note: The HFS file system has been obsoleted in HP-UX since version 10, except for the /stand file system which contains the kernel, and you’re not going to unmount the kernel and run a file system check. Instead, get to single user. Here is one way:
# reboot
# interact with IPL . yes
ISL>hpux -is
And as the kernel is loaded vg00 will be enabled and automatically checked for corruption.
# init 2, same thing, automatically check run level 2
# init 3, same thing, automatically check run level 3, multiprocessor mode. The system is up.
NEVER! fsck /stand – The only hfs file system for over a decade is /stand, and you never fsck /stand!
thanks for HP/UX JFS repair commands :)
Concise, very effecive and to the point. Just what was required.
excllent work
What about to recover data that are deleted?
Thanks anyway… :)
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Thankyou – this page saved my life! (well, not literally). After checking loads of links that just told me what it said in the man page, here was a quick, easy and practical way to use the command.
How do you check the / partition – which cannot be unmounted since it still shows as “in use” after going to run level 1? Is there a way without rebooting?
Thanks, very good guide!
@Jack, I think that’s when you need to use a rescue disk. Most of the distros have this on their installation media.
How do you find out what the actual device name is?
This post is over two years old but still relevant today.
I just used most of the steps described here to repair an ext3 partition on my Ubuntu desktop system. Only difference being I did not do “init 1″. I logged out to the gdm screen then did Ctl-Alt-F2 to get to a virtual console. I logged into the system and ran the commands with the exception of “init 1″.
Thanks for a very helpful and concise article.
Excellent article!!
Is there a way to do this via SSH?
What methods do you recommend for listing the mounted file systems?
Thanks!
system not booting.because new root user created last time,not come guimode .so restart that p.c .not booting asked password or alt ctrl d.so i gave that password .system restarted.what will i do?lasttime i worked that pc du /dev/hdc6 .but i don’t know about this cmd.may be reason is there
Hi I am getting following mesage:
Repair File system 1#
I don’t know what to do now.
Beofore this it is saying file system corrupted. Anybody please help help….
Don’t try that on Ubuntu 10.04.
It will just shut down the system.
Thanks a lot for this helpful article