A while back, I got a Dell XPS machine that came with Ubuntu preinstalled. I’ve been running Arch Linux on most of my machine for several years now, so decided to install Arch Linux alongside Ubuntu.

Fastforward a few years: I’ve been interfacing more and more with Alpine Linux lately and want to try it as a daily distro for a bit, so I’ve decided to replace the Arch Linux install on the XPS with Alpine.

After installing Alpine Linux on a separate partition, I booted back in Ubuntu and, grub-mkconfig -o /boot/grub/grub.cfg but it complained about an unknown filesystem when looking at the Alpine partition. A bit of searching led me to a StackExchange post that mentions:

When an ext4 filesystem has the metadata_csum_seed feature enabled, then grub-install will not work and report this grub-install: error: unknown filesystem error.

[…]

you can disable the feature with tune2fs -O ^metadata_csum_seed /dev/sda1

When running the tune2fs command, I was greeted with:

tune2fs: Filesystem has unsupported read-only feature(s) while trying to open /dev/sda1

It turns out that the version of tune2fs on Ubuntu is older than the one that ships with Alpine Linux, so I booted the Alpine Linux live USB I had around from the install, ran the tune2fs command, booted back in Ubuntu and then grub-mkconfig ran properly.