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Ubuntu 12.04LTS

After an automatic kernel update through update-manager I cannot boot up without intervention any more. Latest version which GRUB boots automatically is 3.2.0-64-generic-pae which fails during startup at a blank screen.

[ 2.140928] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (0,0)
[ 2.141024] Pid: 1, comm; swapper/0 Not tainted 3.2.0-64-generic-pae #97 Ubuntu

followed by a call trace, found at the end of the bootup in recovery mode.

It is not a disk error as I bootup properly with both 63 and 29.

May be the same as I want to recover my data on Ubuntu but maybe not. Others get the same message for unrelated (?) problems.

Another post has a reply which suggests it might be the boot cd - my cd has simcity in it - a wine project I am working on - getting it working !!

I am obliged to use 3.2.0-63-generic-pae in order to bootup properly.

How can I remove 64 and automatically bootup 63? I presume I have to edit a GRUB script but which and where is it?

If I physically remove 64 (how? which of the two shown below? do I need to make a new "generic" image?) will I then be deprived of future kernel updates which depend upon 64?

harveyp@harveyp:~$ sudo dpkg -l | grep linux-image
[sudo] password for harveyp:
ii linux-image-3.2.0-29-generic-pae 3.2.0-29.46 Linux kernel image for version 3.2.0 on 32 bit x86 SMP
ii linux-image-3.2.0-63-generic-pae 3.2.0-63.95 Linux kernel image for version 3.2.0 on 32 bit x86 SMP
ii linux-image-3.2.0-64-generic-pae 3.2.0-64.97 Linux kernel image for version 3.2.0 on 32 bit x86 SMP
ii linux-image-generic-pae Generic Linux kernel image

Which kernel version to use ... has a reply which suggests ...

sudo apt-get purge linux-image-X linux-headers-X where X is the version that is giving you issues

but here too I am unsure what to do about the "generic" image as I have a pae 64 and a generic 64. And I don't wish to break it any more than it is already ...

Thank you for your help.

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Perhaps consider just updating your system with apt-get update && apt-get dist-upgrade ? Your 3.2.0 kernel is quite old. The latest 12.04 kernel is 3.13.0-29. –  bain Jun 8 '14 at 14:14
To remove the -64 kernel just dpkg -P linux-image-3.2.0-64-generic-pae –  bain Jun 8 '14 at 14:16
Unfortunately I have not succeeded in loading either 13.10 or 14.04. Indeed later 12.04 distros fall over on my machine ... When I win the pools ... –  HarveyP Jun 12 '14 at 22:37
The version which always loads for me without fail is 3.2.0-29 ; I have an unsupported motherboard from SiS. How would I go about getting a later kernel like 3.13.0? Just to test it you understand - I don't expect it to work ... –  HarveyP Jun 12 '14 at 22:44
Your motherboard will work fine. Unless you mean you have sis graphics, in which case it might not work. If you have an old PC and an unsupported graphics card the easy option is to replace the card with a supported graphics card. Old secondhand video cards are pretty cheap. The quickest way to test is to boot one of the installer images. –  bain Jun 13 '14 at 0:42

1 Answer 1

up vote 0 down vote accepted

To remove a new linux kernel version (for example linux-image-3.2.0-64-generic), use the following command:

sudo apt-get purge linux-image-3.2.0-64-generic linux-headers-3.2.0-64-generic linux-headers-3.2.0-64

This command will remove the kernel and associated headers and then update the GRUB boot loader. Subsequent boots will use the most recent previous kernel version on your system.

With kubuntu 12.04 and linux-image-3.2.0-64-generic I discovered that my windows applications would no longer run using crossover office. Hence I downgraded to 3.2.0-63.

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