How to upgrade to latest kernel of Ubuntu 14.04.3 LTS or 14.04.4 LTS from Ubuntu 14.04.2 LTS

Ubuntu 14.04 LTS is a Long Term Support version of the Ubuntu Linux Operating System. Over time, Ubuntu releases point updates to it. Currently, the point update is at Ubuntu 14.04.3 LTS. When you update your Ubuntu packages using:
$ sudo apt-get update <enter>
$ sudo apt-get dist-upgrade <enter>

you will find that you are automatically upgraded to the next point release i.e. Ubuntu 14.04 LTS gets updated to Ubuntu 14.04.3 LTS. Open a terminal window and check the release of your system using:
$ lsb_release -a <enter>
at the end of the output of above command, you will see:
Distributor ID: Ubuntu
Description: Ubuntu 14.04.3 LTS
Release: 14.04
Codename: trusty

This output description shows you updated to Ubuntu 14.04.3 LTS. However, open a terminal window and check the kernel installed using:
$ uname -a <enter>
Linux rm01 3.16.0-60-generic #80~14.04.1-Ubuntu SMP Wed Jan 20 13:37:48 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

the command returns the the kernel version 3.16.0-60-generic, whereas the kernel for Ubuntu 14.04.3 LTS is 3.19.0-49-generic.

Using the updated 3.19.0-49-generic provides better new hardware support. However, Ubuntu does not automatically upgrade the kernel.

Before trying the next step, take a data backup.

Note that when the distribution point release is upgraded, it does not upgrade the kernel version automatically. To do that open a terminal window and install the new kernel manually using:
$ sudo apt-get install --install-recommends linux-generic-lts-vivid xserver-xorg-core-lts-vivid xserver-xorg-lts-vivid xserver-xorg-video-all-lts-vivid xserver-xorg-input-all-lts-vivid libwayland-egl1-mesa-lts-vivid linux-signed-generic-lts-vivid <enter>

Note that I have added linux-signed-generic-lts-vivid because it is needed if you boot using UEFI. If you do not, you need not update it.

If you need to upgrade to the later kernel shipped with Ubuntu 14.04.4 LTS (Wily Werewolf), you can replace “vivid” with “wily” in the above command.

Reboot the computer and check the kernel installed using:
$ uname -a <enter>

You should now see that you have the latest kernel installed. You can also install Ubuntu 14.04.3 LTS by downloading the ISO CD, but for that you have to format your system and do a full re-install.