"kernel Panic" When Booting...

Hi all,

I recently when down to CompUsa and bought an 80 gig external hard-drive and a copy of SuSE Linux Personal 9.1, because everyone recommended it to me as the best Linux distro. I've fooled around with Fedora Core 1, but I have hardly any Linux experience. I connected the new external hard-drive via a USB port, and booted up the SuSE Installation CD. I installed SuSE onto '/dev/sda'. Everything went fine, and when it was done installing it said it would boot again. I selected "Linux" from the boot menu, and it begin to boot. Then it got to "searching for device /dev/sda6". It paused for a few minutes, and then gave me a "Kernel Panic" error saying that it couldn't find /dev/sda6. I've tried reinstalling it three times. Any ideas?

Thanks for the help!

EDIT: I forgot to say, I have a Dell Inspiron 1100 (notebook).

I believe the problem may be due to lack of USB support when booting.
Does the BIOS on your laptop allow you to boot off a USB device?
If not then it is unlikely you can boot off the external hard drive.
Did you install the boot loader in the MBR on /dev/hda?
If so the kernel panic messgae is probably due to the boot loader being unable to find the kernel.
Even though a boot loader can boot a SCSI hard drive (all devices starting with /dev/sd are scsi discs) I don't believe you can boot a USB disc from the boot loader because of the lack of USB support at that level. USB drivers etc are loaded by the kernel. Therefore if the boot loader cannot load the kernel there is no USB support.
External discs attached through USB pretend to be SCSI discs. Hence the SCSI device name.
A possible remedy would be to create a boot or / (if you don't separate /boot from /) partition on /dev/hda and install the kernel there (< 1GB should be plenty, there is an application called ntfsresize that may help however it is not for the faint hearted and backing up is a really good idea). This may give you enough support to boot from the external hard drive.
A possible solution to get around the booting issue is to boot off the CD/DVD and run the installer again. Just prior to configuring the installer you should be presented with an option to boot an existing installation. Select this and hopefully you can load the OS from the external hard drive. My assumption is that if the installer knows about USB to install Linux there then it should be able to load the OS from a USB drive.
I am not 100% sure about the lack of USB support at the boot loader level. There may be some fix out there you never know you luck.

paul,
thank you for the quick response!

I do have the option to boot from a USB device. I didn't mess with the partitioning much when installing SuSE, and I believe the bootloader is installed on my internal hard-drive. Looking at my partition table, it appears that I still have 25 free gigs on my internal hard-drive from where Fedora got installed (somehow Fedora was removed during the SuSE install), and I think I'm going to install suSE onto that free partition, and then use the external hard-drive simply as an extension for SuSE to store more files on.

Much thanks for the help, I'll be posting here if I have any problems, which is definitely a distinct possibility.

Cheers,
Niels

You may find Fedora is still installed on your drive. The boot loader doesn't know about it thats all. You should be able to mount the Fedora drive from the CD/DVD rescue mode and copy move files first if you want.

I have a Dell laptop too and I use my external drive for storage only. I have never tried installing SUSE there. My laptop is a couple years old now and doesn't allow for booting off USB in the BIOS.

Anyway good luck!. :-)

Ok, I'm posting this from another computer, but I will be on the lookout for replies! So, I decided to instead install the boot-loader on the external hard drive. So I chose to install GRUB on /dev/sda. When I booted, it said "GRUB..." and then just stayed there. Ok. So I decide to install LILO instead just for the heck of it. I install LILO on /dev/sda and boot onto a "USB Device". It pulls up the boot loader just fine! Great, I say to myself! I select "Linux". Well, during the process of booting, it spits out the following error:

"Kernel Panic. Unable to mount root fs on unkown block (8, 6)."

Oh no, back to square one I think. So I decide to boot up Windows to go post on the SuSE support forums. So I select "Windows" from the boot-screen this time. It says "Loading Windows..." and thne just stays there. I've waited half-an-hour, and as I type this it still says "Loading Windows..."

Any suggestions on how to fix this? I would like to avoid reinstalling Windows if possible...

Your help is VERY much appreciated!

Cheers,
Niels

Does you laptop have an option to boot from a USB device?
If so you may need to change this back to boot off the internal hard drive (only change this if you have changed the setting in your BIOS).
Otherwise I have a funny feeling you have over written the boot loader on the internal hard drive and not onto the external hard drive.
To fix the Windows boot environment you can boot off the Windows XP CD and run the Recovery console. The two commands that you will need are fixmbr and fixboot.
Run fixboot followed by fixmbr. Fixboot rewrites your boot sector and fixmbr over writes your existing mbr with a known Windows mbr. This will remove the current boot loader and default to a Windows boot loader.

It may also be worthwhile disconnecting your external drive/drives during this process so nothing on the external drive is damaged.

"Kernel Panic. Unable to mount root fs on unkown block (8, 6)." means it cannot find the device the root partition is on. If you do ls -l against /dev/sda6 (assuming 6 is your root partition) you should see two numbers in the middle of the output separated by a comma. These are the major and minor numbers. If they are the same as 8,6 then the boot loader doesn't know how to find the partition it thinks the root partition is on. Hence a kernel panic. I would say this is due to the lack of USB support at the boot loader level and/or partition 6 being a logical partition.
Major and minor numbers are used by the kernel to to identify hardware. These are fixed by the kernel developers. For example a major number of 8 may be the device name /dev/sda where 6 is the partition number. I believe there is a document that details these in /usr/src/linux.

If your / or /boot partion is on partition 6 this could also cause boot issues. Normally only a primary partition (numbers 1 to 3 and maybe 4) may be booted.

paul,
thank you very much! You've been a great help all day. As soon as I find the recovery CD, I'm going to restore the boot loader. I think I'm also going to wipe my external drive clean of SuSE and start the installation completely anew.

Then I'm going to try installing the bootloader on /dev/sda again, and see how it works. If it doesn't work...I'll cross that brige if I come to it.

Cheers,
Niels

Good luck. I hope it all goes well. If you get SUSE working on the external drive please let me know as I would be interested in doing something similar myself.

Ok,
well, I did exactly what you said. Now when I boot my computer it says "NTLDR is missing. Press any key to restart". When I press a key I get the same error message.

D'you have any advice? I would like to keep from reinstalling Windows if at all possible. Thanks.

The Windows partition may not be active and its looking for ntdlr in the wrong partition. I'd suggest booting off the Linux CD and at the CD boot prompt select rescue. Log in and type fdisk -l /dev/hd? and fdisk -l /dev/sd? and post it. If there is an asterix next to the Windows partition then its active. If there is another partition that is active that needs to be fixed. If you can mount the Windows partition in rescue mode and check to make sure cntldr is present and cboot.ini it present. Please send me the contents of cboot.ini. Thanks.

Boot off CD or DVD select rescue mode or if just at the boot prompt:

boot: linux rescue

After logging in (please send output of following):

# fdisk -l /dev/hd?
# fdisk -l /dev/sd?

# mkdir /a
# mount -o ro -t ntfs /dev/hda1 /a
or if Windows is FAT

# mount -t vfat /dev/hda1 /a

where /dev/hda1 is your Windows partition

# ls -la /a

ntldr should be there

# cat /a/boot.ini

In the XP Recovery Console there is a command bootcfg. It may also be worthwhile running it as follows and sending me the output

bootcfg /list

help bootcfg gives other options. I have never used this command however it may help fixing your boot environment. You may have to run fixmbr and fixboot after running bootcfg. I'd try on thing at a time.

May be worthwhile reading http://support.microsoft.com/default.aspx?...kb;en-us;812492 not a lot of info though.
Something may have gone wrong when the linux boot loader was reinstalled.