8.10 upgrade Kernel Panic - not syncing: VFS:

[ardencaple]

[SOLVED] I have just attempted to upgrade from 8.04 to 8.10

Everything seemed to go OK during the upgrade process, but on reboot I get:

Kernel Panic - not syncing: VFS: unable to mount root fs on unknown-block (0,0)

I have had a look at some forum entries, and I think this may be because there is no initrd.

in /boot there is no initrd.img file corresponding to the kernel (2.6.27.7-generic?), nor are there any initrd lines in /boot/grub/menu.lst

So: I guess my questions are:-

1. is the initrd the problem?
2. how can I fix it?
(If I need initrd-tools - they don't seem to be present)

I can boot using the previous kernel 2.6.24-21, but I don't have any networking

My hardware is a Lenovo N200 3000 laptop with a T8100 processor.

Rob MacAulay

[SOLVED - see posts below. Unfortunately there are other issues lurking behind this one..]

[tommcd]

1. is the initrd the problem?
2. how can I fix it?
(If I need initrd-tools - they don't seem to be present)

I can boot using the previous kernel 2.6.24-21, but I don't have any networking


1. It could be an initrd problem.
2. I don't have initrd-tools on my Intrepid system, so I don't think that is the problem. In fact, running:

apt-cache search initrd-tools?
returns nothing. So I don't know what that is.


To create a new initrd for the 2.6.27-7-generic kernel:
Boot from the 2.6.24-21 kernel. Open a terminal and run:

sudo update-initramfs -c -k 2.6.27-7
This should update the initrd for the latest (2.6.27-7) kernel.
(I'm not sure if you need to add the word generic after the 2.6.27-7 in that command. If you get errors, or the kernel won't boot, then repeat the command like this:

sudo update-initramfs -c -k 2.6.27-7-generic
Read the man page "man update-initramfs" for an explanation of that command.

Then add this initrd line to the grub entry for the 2.6.27-7 kernel, right below the kernel line:

initrd /boot/initrd.img-2.6.27-7-gereric
Then try and reboot into the 2.6.27-7 kernel.

I don't know about the networking problem. If you can boot the 2.6.27-7 kernel, then perhaps start a new thread about the networking problem.

[ardencaple]

Thanks -

This generated the correct initrd.img :


sudo update-initramfs -c -k 2.6.27-7-generic

Then I modified /boot/grub/menu.lst to add the initrd entry to the new kernel boot items:


initrd /boot/initrd.img-2.6.27-7-generic

The system then booted normally. So that solved that problem...

I still have some other issues though, so presumably the above was just one symptom of a failed upgrade.

Just for the record, I know about:-
no networking
GNOME power management incorrectly configured

I will probably need to try to do a complete desktop install from scratch to fix these issues though - I can't see any clues to a common cause, so I guess there were several glitches during upgrade.

Anyway, many thanks for the post - I did try to fnd out how to regenerate the initrd.img files, but I would never have found out the magic incantions without your help.

Rob MacAulay

[remco_t]

I have just done a fresh install of 8.10 on a LaCie external USB HDD with Fujitsu internal 2.5" drive. I've set up 4 partitions on the drive;

"/"
"/boot"
"/home"
and a FAT32

I'm fairly new to Unbuntu (or any other distro for that matter) and I finally managed to install it to the drive to get beyond the usuall newbie grub errors. Now my booting system is getting stuck on the kernel panic alert.

I've tried

sudo update-initramfs -c -k 2.6.27-7-generic
but then the terminal tells me that the command is disabled since I'm running from a Live CD... Any ideas?

[hatemben]

I just had similar issue and solve it, seems that ubuntu 8.10 did not upgrade correctly. So I have rebooted with old kernel and run


sudo dpkg --configure -a

This should fix the problem, reboot and you are done.

[hitodenashi]

Thanks -

This generated the correct initrd.img :


sudo update-initramfs -c -k 2.6.27-7-generic

Then I modified /boot/grub/menu.lst to add the initrd entry to the new kernel boot items:


initrd /boot/initrd.img-2.6.27-7-generic



Yup, that did it for me too, but in my case it was a newer kernel. For other people running into this problem, be sure to substitute 2.6.27-7-generic with your kernel version.

But, alas, my Ubuntu has not yet booted, as it hanged somewhere further along the line, but at least I'm making progress. I'm sure in a week or two I'll be running 9.04. Yei!