[ "$broadcast" = 1 ] && broadcast="-B" || broadcast=
[ -n "$clientid" ] && clientid="-x 0x3d:${clientid//:/}" || clientid="-C"
[ -n "$iface6rd" ] && proto_export "IFACE6RD=$iface6rd"
+ [ -n "$iface6rd" ] && append dhcpopts "-O 212"
[ "$delegate" = "0" ] && proto_export "IFACE6RD_DELEGATE=0"
proto_export "INTERFACE=$config"