When you update Ubuntu, not all obsolete packages and kernels are removed. Some will stay on your computer taking up spaces and not being used. Your Grub boot menu also have older OS Kernels listed. In this tutorial, I’ll show you how to remove old kernels and update your grub menu to only show your lived kernel.

Getting started:

To get started, first out your current kernel version. Go to Applications –> Terminal

Type the below command to find out your lived running kernel. Take notes of the underlined line. It’s your lived kernel.

uname -r

Next, press Alt-F2 on your keyboard, then type the commands below and click Run:

gksu synaptic

Then type the first three dotted digits of your current kernel in the search box and look for the one that matches your lived kernel.

Now scroll down and remove all kernel versions that are lower than your lived kernel version. You can tell by looking at the last digit.

Right-click on the kernel and select ‘Mark for Complete Removal’

Then click Apply

After removing, go to the terminal and type the below commands to update grub2:

sudo update-grub2

That’s all to it.

Enjoy and please come back soon.