Help for Corrupted Root password

Jazinator · 12-10-2004, 09:29 PM

Hi all,

I had a power outage yesterday and the system shut down right in the middle of booting up. When the power came back on Linux would boot up, but I could not log in as root any more. somehow the password got corrupted or lost or something. It will let me log in as a user, but it won't let me change any configuration files or change the root password from there??. Is there anything I can do to repair this short of reinstalling the whole thing again??

wmakowski · 12-10-2004, 10:19 PM

It would be easier if we knew what distribution you are using. You can set that in the User CP.

You can try using your install CD to boot. When you get to the point where it asks if you want to install there is usually an option to rescue or repair. If this works like it did with my distribution, eventually you will get to a command line where you can chroot to your normal / and then reset your password.

Bill

student04 · 12-10-2004, 10:25 PM

With LILO or Grub, you may have the option to select "single". If you do, select it, and it will boot up into a console, with you as root. Then just type "passwd" to change it.

Otherwise, you may try booting with a linux bootable cd and mount the partition. Then you can generate the MD5 encrypted key via a console (or whatever encryption is used) and paste it into your /etc/passwd or /etc/shadow file (use the latter file if you have it) into the appropriate place.

Jazinator · 12-11-2004, 05:08 PM

I do appologize. I am using RedHat 9 (Shrike) distribution. I will try the suggestions that you have provided so far, if I still can't get it, I will let you know. Thanks again. Jaz.

wmakowski · 12-11-2004, 09:06 PM

You should have no problem with either solution. Alex has a good suggestion with going into Single user mode. You can do that by temporarily editing grub during boot up. When grub comes up use the E key to go into edit mode. You'll see the lines that make up the boot commands. Edit the line with vmlinuz in it to include a 1 right after vmlinuz (see below). Then use the B key to boot. Once the command line comes up you can change the password on root with the passwd command.

Code:

	
	kernel /boot/vmlinuz-2.4.20-28.7 ro root=/dev/hda2 hdc=ide-scsi
	kernel /boot/vmlinuz-2.4.20-28.7 1 ro root=/dev/hda2 hdc=ide-scsi

Bill

aunlead · 12-12-2004, 01:32 AM

was wonderin if above ^^^ method might also work with lilo???...or is it only for grub....

Jazinator · 12-12-2004, 09:17 AM

Thank you guys, that worked great and I learned something new. I was able to edit the Grub loader and boot into run level 1 and change the password. I am so greatful for this site and everyone here. Thanks again Mr. Makowski and Student 4 for you help. Jaz

wmakowski · 12-12-2004, 10:06 AM

Jaz, glad to hear everything worked out. In my opinion this is one of the best sites out there for getting help with linux.

aunlead, I can't give you the exact steps for lilo, but I know it is possible to do the same thing. I know the latest version of lilo is not like the one I run on my old 386. In my version all I had to do was type linux 1 when it came to the lilo prompt and it would continue into single user mode. You might check out the LILO mini-HOWTO at the linux documentation project for more help.

Bill

student04 · 12-12-2004, 01:55 PM

It was a pleasure to help.