option dhcp6.bootfile-url code 59 = string;
option dhcp6.client-arch-type code 61 = array of unsigned integer 16;

if option dhcp6.client-arch-type = 00:07 {
        option dhcp6.bootfile-url "tftp://[2a06:5841:1337::2]/bootx64.efi";
} else {
        # support a hypothetical BIOS system that can PXE boot over IPv6
        option dhcp6.bootfile-url "tftp://[2a06:5841:1337::2]/pxelinux.0";
}