wget -c "https://boot.netboot.xyz/ipxe/netboot.xyz.lkrn" -O /boot/netboot.xyz.lkrn && \
cat > /etc/grub.d/40_custom <<EOF
#!/bin/sh
exec tail -n +3 \$0
menuentry 'netboot.xyz' {
    set root='hd0,msdos1'
linux16 /netboot.xyz.lkrn
}
EOF
update-grub