Comment 5 for bug 2034253

The path on the ESP is constructed from GRUB_DISTRIBUTOR, which in /etc/default/grub is set to:

GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`

So first, 'Debian' is not a reasonable fallback on Ubuntu. The fallback should be Ubuntu.

And second, the lsb-release package is not guaranteed to be installed whenever grub-install is called, because grub2-common does not depend on it. It's part of the minimal seed, but the buildd images don't use the minimal seed; they subset it.

Rather than depending on lsb-release, however, we should just change this to use the not-deprecated /etc/os-release interface, e.g.:

GRUB_DISTRIBUTOR=`. /etc/os-release && echo $NAME || echo Ubuntu`