On Mon, Apr 24, 2023 at 08:56:45AM +0200, Ingo Weinmann wrote: It should be, depends where or if the FAT filesystem is mounted by virt-customize, which depends on the guest /etc/fstab. Anyway this is certainly possible using guestfish directly, eg if the FAT filesystem was the first partition on the first disk then: guestfish -a foo.img -m /dev/sda1 upload cmdline.txt /cmdline.txt See also: https://libguestfs.org/guestfs.3.html#uploading https://libguestfs.org/guestfish.1.html https://libguestfs.org/virt-copy-in.1.html Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-builder quickly builds VMs from scratch http://libguestfs.org/virt-builder.1.html