Comment 8 for bug 1627402

This bug impacts me as well.

I am not able to build an image with grub2 element.

disk-image-create ubuntu baremetal dhcp-all-interfaces grub2 devuser > my-image

I get the following error -

Creating config file /etc/default/grub with new version
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).
dpkg: error processing package grub-efi-amd64 (--configure):
 subprocess installed post-installation script returned error exit status 1