How can I use Kernel 3.19 in 14.04 now?

So I'm rebuilding my storage server. For stability, I want to use Ubuntu server 14.04 LTS as the OS. However, I'm planning to use Btrfs with RAID 5, and this has been greatly improved in kernel 3.19. So I want to use that kernel with 14.04.

I know that 3.19 is the kernel that will be used in 15.04, and is scheduled to be released in August as a HWE kernel and the default for 14.04.3. But I need to build this server now.

I don't want to get into funky custom set-ups that will break things in future. So what is the most trouble free way I can use that kernel now on top of a 14.04.2 installation, that can be easily reverted to standard in August, when I can dist-upgrade to 14.04.3 and get the kernel I want as standard?


You can install a newer kernel

  • as described in Kernel/MainlineBuilds or

  • in this case more simply with the packages built from linux-lts-vivid from the trusty-updates repository:

    sudo apt-get install linux-generic-lts-vivid
    

    This meta-package always depends on the most recent version of Canonical's v3.19 kernel branch.

    The equivalent for the v4.4 kernel branch of Ubuntu Xenial is linux-generic-lts-xenial (what a surprise).

Since kernel packages of different branches don't replace each other, there is virtually no danger, that either of the above steps will make your system unbootable¹. If the newly installed kernel doesn't run, you can select to boot different/previous kernels in the GRUB menu during boot.

¹ The most notable exception is a broken GRUB configuration. If update-grub (called by the kernel package post-installation and post-removal scripts) doesn't work without the new kernel, it won't work with the new kernel either.


You can now install the "latest" (3.19) Ubuntu kernel directly from the repositories:

sudo apt-get install linux-image-generic-lts-vivid linux-headers-generic-lts-vivid

This will install stable Ubuntu kernel for Vivid. And the headers that are needed for building several modules on your system.

Hope this helps!