[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/Office 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 it 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 eth1.2 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, etc.


5) Multiple LANs:

SCENARIO: I have 1 xDSL for Internet access and my intranet is segmented 
to 2 LANs. LAN-1 has Internet access, LAN-2 runs internal servers. I 
configure xDSL and LAN as per SCENARIO 1. In addition I configure Red 
Ethernet as LAN2 which is routable from LAN 1 but does not have access 
to the Internet via xDSL + pppoX-wan WAN (Masquerade or SNAT).

STATUS: as per 3, the Red Ethernet configuration is achieved only with 
manual file editing and workarounds.


6) 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


7) 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 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, 4, 5 and 6 describe what are my current use cases

In my 3 and 4 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 6, where I want to bridge my Red Ethernet to 
extend the ports on the switch, I need this to work (FS#390).

SCENARIO 7, which is the one you might be trying to cover, is the least 
important to me given this router supports xDSL extremely well.


I hope this helps.

Mauro