WAN port with PPoE and VLAN configured won't connect without use of switch in front of it.

Hi there,

I have a FFTH connection from my ISP (KPN, the Netherlands), from which I get a PPoE connection with VLAN (Id 6). I am trying to set up the WAN connection on a minipc, but I won't get it done, without the use of a switch with VLAN tagged in front of it. 
When searching for an solution I get 2 possible solutions that both are not working for me, without using the switch.

Scenario
MiniPC
Port1 LAN DHCP
Port4 WAN PPoE with VLAN (id 6), ISP cable directly connected to it. 
use a Netgear managed switch with VLAN6 tagged on ports (802.1Q) for getting my connection to work. (but I don't want to use this switch).

suggested solution 1:

Port4
created extra zone: "WAN_Physical" and linked port4 to this zone.
Gave that zone Static IP: 1.1.1.2/24
Attached to Port4 I created a VLAN6 and connected it to zone WAN. It's a PPoE connection.
Internet cable directly attached to port4: No connection
Internet cable attached to switch which has VLAN6 Tagged on ports and from there to port4 I get internet connection.

suggested solution 2:
(preffered scenario, because of the simple construction)

Port4
WAN interface
PPoE setup
DSL Settings: Add VLAN Tag:6
Internet cable directly attached to port4: No connection
Internet cable attached to switch which has VLAN6 Tagged on ports and from there to port4 I get internet connection.

In both cases when the internet cable is directly connected to port4, I get the notification in the logging:
PPPoE
Port4.6 : PADI Packet sent from interface
17955

Any help is appriciated

Thanx in advance.

Mathieu