# apt install dropbear-initramfs -y"
# echo 'DROPBEAR_OPTIONS="-RFEsjk -c /bin/cryptroot-unlock"' > /etc/dropbear-initramfs/config
# echo 'PASTE YOUR PUBLIC KEY HERE' > /etc/dropbear-initramfs/authorized_keys
/etc/default/grub
: GRUB_CMDLINE_LINUX_DEFAULT="quiet ip=192.168.1.81::192.168.1.1:255.255.255.0:luks:ens4:none:"
# update-grub && update-initramfs -k all -u
Merci à Neil Brown pour son aide.