AT&T fiber, WRT3200ACM, bridge-mode?

Installing and Using OpenWrt Network and Wireless Configuration
1

Hi,

I'm trying to wrap my head around using eap_proxy. How should I modify the VLAN setup such that the first port of the switch (eth1.4?) is dedicated for the residential gateway (an Arris BGW510 in my case)

2

Is it even possible to change the role of just one of the switch ports?

3

Could a Linksys USB3GIG USB 3.0 Gigabit Ethernet Adapter be a possible solution to gain an extra port?

4

You can separate any of the LAN ports into an independent interface. Create a new VLAN 4, add both the LAN4 port (untagged) and the CPU1 port (tagged), take the LAN4 port out if the current VLAN, and you can now use eth1.4.

5

mwan3 tutorial teaches how to remove a port from LAN and then turn it into a WAN.