Hm, actually loop doesn't work well either, because the same piece of code tries to access /dev/loop01 instead of the actual /dev/loop0p1
Once I fix that, it still later fails with: Exec: ['blkid', '-c', '/dev/null', '-o', 'value', '-s', 'UUID', '/dev/loop0p1'] Installing GRUB for BIOS ERROR: Do not understand partition device name /dev/loop0p1 ERROR: Exception('Do not understand partition device name /dev/loop0p1') Something went wrong, cleaning up! I found in the code that I could override that in the grub plugin by specifying: image-dev: "/dev/mapper/vg0-myvm--root" However, even this failed with: 2021-10-16 22:09:37 INFO Exec: ['chroot', '/tmp/tmpy9lcantw', 'grub-install', '--target=i386-pc', '--no-nvram', '--force-extra-removable', '--no-floppy', '--modules=part_msdos part_gpt', '--grub-mkdevicemap=/boot/grub/device.map', '/dev/mapper/vg0-myvm--root'] 2021-10-16 22:09:37 DEBUG STDOUT: 2021-10-16 22:09:37 DEBUG STDERR: Installing for i386-pc platform. grub-install: error: diskfilter writes are not supported. 2021-10-16 22:09:37 ERROR Program failed: 1 So, uhh, I'm a bit stuck here. This used to work under vmdebootstrap... -- Josip Rodin