As the title asks; how do you add a second WAN port?

I thought it was as simple as adding an interface with the correct vlan settings, but maybe I'm missing something.
Has anyone successfully done this?

First of all what hardware? Do you want a second wan port in the same vlan as the existing wan port or do you want a new vlan? If you want a second wan port in the same vlan as your existing wan port all you should have to do is move whichever port you want out of the lan vlan (vlan0) into the wan vlan (vlan1). Keep in mind the internal port numbers do not necessarily match the numbers on the back of the case. If you want a new wan port just create a new vlan and move whatever port you want into that new vlan (I do that for my DMZ ports).

Just keep in mind that on some chipsets the wan port connects directly to the main CPU while the lan ports connect to a switch chip before the main CPU.

I recently build an image with working dual wan connection. In a nutshell this is what i did:

Build an image from trunk and selected ip and m-route as extra package.
Setup basic lan networking using network config file
Add two new vlans (one for each switchport) using network config file, which are directly connected to cpe devices from your provider.
Add two new interfaces using network config file (i named them isp1 and isp2)
Make sure mroute package is at first disabled using mroute config file
Reboot and see if local connectivity is still ok on all ports (lan and the two new wan's)
Check routing table to see if two seperate default gateways exist!
Edit mroute config file to your needs and set enabled
Edit firewall config file and add entries for the two new interfaces
Reboot and you're ready to go.

And if all is working ok, you could even remove the standard wan interface config...

Good luck

(Last edited by Adze on 10 Mar 2010, 19:07)