[LEDE-DEV] FS#490 - BT Home Hub 5 Ethernet WAN Port configuration

[Mauro M.]

In response to Mathias:


Let's have a look at the use cases for the Red Ethernet Port:

1) Classic case: Internet Home user with xDSL WAN + Wired and Wireless 
Devices

SCENARIO: In this case my WAN is the xDSL port, my router has 4 Ethernet 
(yellow) ports, but I have 5 devices, so I want to BRIDGE my Red 
Ethernet to extend the available Yellow Ethernet (LAN) ports

STATUS: this does not work today, see FS#390


2) Small Office User with xDSL and Fixed IP Subnet

SCENARIO: In this case I have to disable Masquerading for my servers on 
the subnet to be addressable, also in this use case scenario I have 5 or 
more wired servers and I want to extend my switch to bridge the Red 
Ethernet port

STATUS: as above this does not work today FS#390


3) Small Office User Intranet: this extends SCENARIO 2

SCENARIO: I use a second router, the Red Ethernet (that I name "ewan") 
is connected to my router at (2) and is assigned a fixed IP on the 
subnet. The Yellow Ethernet switch is bridged to WiFi as "LAN". The 
firewall is configured to SNAT LAN to EWAN.

STATUS: today this works by editing /etc/board.json to add port 5 to the 
switch, adding a new VLAN to Switch0 to cover port 5, creating a new 
network interface EWAN. However it works only if I create a bridge 
br-ewan and I add eth1.2 to it, it does not work if I configure eth1.2 
directly to EWAN. I would like eth1.2 to be available in the list of 
interfaces (now I have to "know" that it exists and I have to configure 
it manually). Newbies might bang their head trying to use eth0.2 which 
is created by the additional VLAN, but it does not work.


4) Small Office Multi Wan: this extends SCENARIO 2 and 3

SCENARIO: I have 2 xDSL WANs, one is as at (2), the second is an xDSL. 
The WAN port on my router is  configured as ADSL with 
pppoa-wan/pppoe-wan. The EWAN is connected to a router with Internet 
access and is assigned a fixed WAN IP.

STATUS: as per SCENARIO 3, the Red Ethernet is configured manually by 
editing /etc/board.json


5) WiFi repeater: I configure the router just as a WiFi repeater, I need 
extra wired ports and I want to bridge the Red Ethernet to my LAN

STATUS: as per SCENARIO 1 and 2


6) Home or Office user with separate xDSL Modem

SCENARIO: I have an xDSL modem and I want to use pppoe over the Red 
Ethernet

STATUS: I have never tried this scenario, but I believe this is what is 
covered by the default configuration on most routers with Ethernet WAN 
(I wonder why since I find this the least useful use case) and thus it 
is supposed to work


SCENARIO 3 and 4 describe what are my current use cases

In my 2 use cases it does not really matter whether the Red Ethernet is 
recognized as WAN. In case 3 it is sufficient that it is configurable 
with an IP, thus, whatever the name we give the interface, I would like 
it to appear by default on a fresh firmware install. To support CASES 1, 
2 and 5, where I want to bridge my Red Ethernet to extend the ports on 
the switch, I need this to work (FS#390)

I hope this helps.

Mauro