password file lost... and disk inaccessible

yosato_uk · 01-14-2007, 12:40 PM

Hi all,

I think I've done drastically stupid ... I have renamed the password file for some reason. The file itself is there with a different name, so it would only be renaming it back, but I can no longer access anywhere as anybody. Would anybody kindly tell me how I could access the root directory somehow?

Regards,
Yo

FnordPerfect · 01-14-2007, 01:37 PM

Don't panic.

* Don't you have a bootable CD with a Linux Live System? Then just mount your root partition and rename it back.

* Which Boot manager do you use? I hope it's grub or LILO. Both give you the ability to pass boot parameters to the kernel.

If you use GRUB, hit Escape to get to the boot menu, select the menu entry, hit e to edit the entry.

If you use LILO, I think you have to hold Ctrl before it loads the kernel...

One of those parameters is "init=" which tells the kernel the first program it should run after it has finished initializing. Normally this is a SysV style init programm, but actually it can be anything!
Just use "init=/bin/sh" and it will start a very basic Root shell, which should be sufficient to rename the file back.

Good luck

pixellany · 01-14-2007, 04:58 PM

The install CD should also allow you to get to a terminal---boot from CD and type ctr-alt-F1 when it finishes loading

trickykid · 01-14-2007, 05:08 PM

Quote:

Originally Posted by FnordPerfect

Just use "init=/bin/sh" and it will start a very basic Root shell, which should be sufficient to rename the file back.

And remember also, some distro's won't mount the / filesystem read-write when you pass init=/bin/sh or init=/bin/bash so in order to mount / which most likely has /etc, do the following:

mount /proc
mount -o remount,rw /

And then you should be able to edit your /etc/passwd file and or restore it, etc.

yosato_uk · 01-15-2007, 07:17 AM

Hi FnordPerfect, thanks for your prompt help,

Quote:

Originally Posted by FnordPerfect

* Which Boot manager do you use? I hope it's grub or LILO. Both give you the ability to pass boot parameters to the kernel.

One of those parameters is "init=" which tells the kernel the first program it should run after it has finished initializing. Normally this is a SysV style init programm, but actually it can be anything!
Just use "init=/bin/sh" and it will start a very basic Root shell, which should be sufficient to rename the file back.

I tried this route: it worked eventually.

I simply put it at the end of kernel line:

kernel /boot/vmlinuz-x.x.x-x ro quiet splash init="/bin/sh"

this got me into the system, though I found it is /root directory (rather than /) which is my original /. Couldn't initially access the directory so tried changing ro to rw. Did work then.

Feel a bit wiser, you saved me, many thanx again.

Yo

yosato_uk · 01-15-2007, 07:21 AM

Quote:

Originally Posted by trickykid

And remember also, some distro's won't mount the / filesystem read-write when you pass init=/bin/sh or init=/bin/bash so in order to mount / which most likely has /etc, do the following:

mount /proc
mount -o remount,rw /

And then you should be able to edit your /etc/passwd file and or restore it, etc.

and of course I forgot to read this, othrewise I could have saved a lot of time... thanx trickykid!