apt-get install gdisk
sgdisk --zap-all /dev/sdb
sgdisk --new=1:0:0 --typecode=1:ef00 /dev/sdb
mkfs.vfat -F32 -n GRUB2EFI /dev/sdb1
mount -t vfat /dev/sdb1 /mnt -o uid=1000,gid=1000,umask=022
* copy files + bootia32.efi
rsync -auv /home/ghusson/Téléchargements/loopmount/ /mnt
* debian : .disk
grub-install --removable --boot-directory=/mnt/boot --efi-directory=/mnt/efi/boot/ /dev/sdb