Re: Kernel Panic for File System, cannot umount / fsck

[Alvin Oga <aoga@ns.Linux-Consulting.com>]

hi ya

On Tue, 18 Jan 2005, Tim Harding wrote:

> I've just received the kernel panic below while performing an rf on
> /home/backup.
> 
> I can read /home.  I can't write to /home.

you have a corrupt /home fs ... and you  told it to remount any
corrupt fs as "ro"

>  I can't umount /home 

you cant unmount if you're logged in as tim

> or
> kill the processing blocking that umount.  I can't run fsck.  How can
> I recover from this situation?

you should NEVER fsck a mounted fs so its right in asking and
warning you NOT to do it

> clark:/home# mount
> /dev/md0 on / type ext3 (rw,errors=remount-ro)

good and bad to remount ro ..
	better to fix it ( during bootup ) ... than to remount-ro

=========

go to single user ... ( init 1 )
	- your raid should have built the raid array
	if its a properly installed raid

	root# e2fsck /dev/md0
	root# e2fsck /dev/md1
	root# e2fsck /dev/md2
	root# reboot

	- if you get too many errors during e2fsck of consecutive
	inodes, you may as well reformat it .. and restore from
	"good backup" ( your backup of corrupt fs will create a 
 	corrupt backup too if you overwrite what was good backup )

- it's a bad idea to use ext3 .. since if ext2 screws up underneath,
  you have to fix it ( ext2 )

c ya
alvin