Edit: /etc/grub.d/01_track_initrdless_boot_fallback (638B)
#! /bin/sh
# # CLOUD_IMG: This file was created/modified by the Cloud Image build process
# This will detect if we attempt to boot with an initramfs and fail.
# In the case of a failure, initrdless_boot_fallback_triggered is set to
# a non-zero value in the grubenv. This value can be checked after boot
# by looking in /boot/grub/grubenv or by using the grub-editenv list command.
set -e
cat <<"EOF"
if [ -n "${have_grubenv}" ]; then
if [ -n "${initrdfail}" ]; then
set initrdless_boot_fallback_triggered="${initrdfail}"
else
unset initrdless_boot_fallback_triggered
fi
save_env initrdless_boot_fallback_triggered
fi
EOF