Here's my situation. I have a Cisco SG300 switch with a bunch of VLANS configured, and I have static route which connect to my Linksys WRT54G. Everything works fine. However, I need to do some port forwarding to a subnet(vlan) thats only my switch. The Linksys does not allow this, port forwarding is only one a local subnet.
I bought this Buffalo N600 with DD-WRT installed, because the sales guy told me it would work. The port forwarding part of it does work, but any client thats on a VLAN cannot get out to the internet. Buffalo support had no idea and DD-WRT forum said its not possible.
I know a Cisco RV180W can do what I'm looking to do, but wasn't sure if anyone knew of a better option? I've heard the Cisco RV devices aren't that great.
VLANs don't traverse bridges, so as long as the port with the uplink to router is on the same VLAN as the clients, that should work...
Ideally you would use a routing device that has two or more "inside" ethernet ports configured - one for the dedicated port forwarding to the correct port on the switch, and a separate one for general internet access. From what you describe and a quick web search I don't think that's possible as I think the N600 cannot address the ports individually.
I'm not that familiar with Cisco, but make sure the uplink port is a member of the client VLANS you want internet access for, and experiment with tagging - should be OFF for that port (but I'm thinking in Nortel terms - Cisco may label differently!).