Try to install grub-pc...

diff --git a/create-image b/create-image
index c2e6139..85c8384 100755 (executable)
--- a/create-image
+++ b/create-image
@@ -140,6 +140,8 @@ class ImageCreator
               File.write "#{dir}/boot/grub/grub.cfg", grubconf.gsub(/#{old_uuid}/, rootfs_uuid)
             end
           else
+            system("chroot", dir, "apt-get", "-qy", "update")
+            system({'DEBIAN_FRONTEND' => 'noninteractive'}, "chroot", dir, "apt-get", "-y", "install", "grub-pc")
             File.write "#{dir}/boot/grub/grub.cfg", <<-EOC
               set timeout=5
               insmod part_gpt