Ubuntu 22.04 desktop installation guide btrfs-luks full disk encryption including /boot

I am a big fan of Willi Mutschler‘s btrfs-luks full disk encryption installation guides on his site, https://mutschler.dev, and have used them for installing Manjaro and Ubuntu 20.04 and newer versions. Recently, I set up Kubuntu 22.04 full disk encryption by following the same guide and noticed a couple of changes that had to be done to get it working. So I am documenting those here till he writes a new guide for Ubuntu 22.04. 🙂

In the step 3 of his excellent guide, the optimized mount options for SSD and NVMe drives are listed. The space_cache option mentioned in that section no longer works on Ubuntu 22.04 because the option has been renamed in the newer versions of the Linux kernel. So one has to specify the option as space_cache=v2. Otherwise, the Ubiquity installer will crash, and the installation will fail.

Also, in the Install the EFI bootloader section, it is a good idea to use the HWE Linux kernel package names corresponding to 22.04 instead of 20.04 since the packages containing the old LTS version in their name are ‘dummy transitional packages’. So the corresponding command can to be updated to

apt install -y --reinstall grub-efi-amd64-signed linux-generic linux-headers-generic linux-generic-hwe-22.04 linux-headers-generic-hwe-22.04

At the time of writing this post, the HWE package installs the same kernel version as the one that shipped with Ubuntu 22.04 since there isn’t a newer kernel released yet – these are usually backported from newer LTS versions.

With these minor changes, it should be possible to follow the steps in that documentation to set up full disk encryption with btrfs and luks on Ubuntu 22.04.

As a bonus, I have used the same guide for installing Kubuntu 20.04, 21.10 and 22.04, with appropriate substitutions, wherever needed.

I have usually skipped the last section in this guide, Install Timeshift, timeshift-autosnap-apt and grub-btrfs, in favour of using my tools of choice to do the same – Snapper and snapper-gui, both of which are available in the official Ubuntu repositories. I will write a blog post about it in the future. 🤞