How can I remove new kernel versions after downgrading?

Question

I upgraded Ubuntu to 12.04, all packages. But after that I encountered a lot of problems so I decided to downgrade to 11.10.

After I did that I found I now have two kernels: 3.2.x and 3.0.x. I found many explanations of how to remove older kernels, but i have no idea how to remove the newer kernel.

I dont see a 3.2 kernel running when im using the 3.0 kernel. But I see it in Grub.

When I type uname -r in terminal I see the 3.0.x kernel which im using at present.

How do I proceed to remove the 3.2 kernel?

Answer 1

There are 3 files you will need to remove, more if you are using a virtual machine too. But these are the main ones.

Open synaptic, use the search to find the installed kernels

• linux-headers-3.2.x.x
• linux-headers-3.2.x.x-generic (possibly generic-pae or i686)
• linux-image-3.2.x.x

Should be easy enough to remove. Afterward run

sudo update-grub

Answer 2

This should remove your 3.2 kernel:

sudo apt-get remove --purge 3.2.x-xx-*

Obviously, replace the x's with the actual version numbers from your 3.2 kernel version. If you don't remember what those numbers are, you should be able to see them by looking in the /boot directory.

The last time I did this, I recall it triggering a grub-update to remove it from the GRUB menu as well.

-This works best for removing newer kernels that you want remove like 3.3.0 +, which would not be found in synaptic, this is a life saver! -Rabbit2190

Answer 3

I think the second will work for you :

1. For uninstalling the kernel run:

sudo apt-get remove linux-image-version_number*
sudo apt-get remove linux-headers-version_number*
sudo apt-get remove linux-image-extra-version_number*     (if applicable)

or simply uninstall them from synaptic/software center.

2. For uninstalling the kernel installed from source, run:

sudo rm -rf /lib/modules/kernel_version
sudo rm -f /boot/vmlinuz-kernel_version*
sudo rm -f /boot/initrd.img-kernel_version*
sudo rm -f /boot/config-kernel_version*
sudo rm -f /boot/System.map-kernel_version*

Finally, after uninstalling the kernel by either one of the processes above, run:

sudo update-grub

to clean the grub menu.