Installing Lubuntu 20.04 with GPT and EFI

I had an existing installation of Lubuntu 18.04 which I wanted to upgrade to 20.04. Lubuntu docs say this requires a fresh install. My previous 18.04 installation was using GPT and EFI. During installation of 20.04 from the live USB I unmounted the previous drive as suggested on this blog post and chose to erase disk so Lubuntu would partition things automatically.

However Lubuntu 20.04 seems to have decided to install as MBR rather than GPT and also no EFI.

No GPT: sudo fdisk -l shows Disklabel type: dos

No EFI /sys/firmware/efi doesn't exist

I'm willing to reinstall but how can I get Lubuntu to install with GPT and EFI? Do I have to manually partition things? Or is there a way to get it to do it automatically?

Solution 1:

How you boot install media, UEFI or BIOS is then how it installs. You must boot in UEFI mode from UEFI boot menu.

Some tools to create USB flash drive installer also only create one or the other. So only create flash drive installers in UEFI boot mode, if using one that only makes one version or the other.

Shows live installer with screen shots. Both BIOS purple accessibility screen & UEFI black grub menu screen, so you know how you booted:

https://help.ubuntu.com/community/UEFI

The new 2020.10 installer now uses grub for both BIOS & UEFI, but seems to want to make all drives as gpt.

Shows Rufus UEFI menu:

Unable to access Ubuntu from UEFI