[SOLVED] ubuntu 10.0.4 gives kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) while booting

ubuntu 10.0.4 gives kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) while booting

Hi i recently installed ubuntu 8.04 on my desktop and in the upgrades menu i gave upgrade to ubuntu 10.04.3 LTS but after installing it started giving me this error

[    0.694063] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

Please help as i am new to ubuntu and also get back to me for additional info if required.

Solution

I will give you one option I know would work, but it involves booting from a full install CD / ISO and using rescue mode to gain access to your boot volume and Grub. Here is what you would do to start.

Boot from a full install CD and choose the menu option for rescue mode.
go to your boot volume where Grub is located, usually in rescue mode your old file system is on /mnt/sysimage
Find and edit /mnt/sysimage/boot/grub.conf to increase the timeout and unhide the menu using the following commands within grub.conf.

Grub.conf

  timeout=20    
  #hiddenmenu

Reboot from the hdd this time and when grub shows up choose the previous working kernel and that should boot. You will be back on a previous kernel and possibly release, but you will have a system to at least back up and retry the upgrade.