I had previously been using a Cisco 871 router as a Firewall/NAT/VPN router with ADSL internet service. The U-verse installation placed a 2wire residential gateway (RG) in between my 871 router and u-verse VDSL2. There is no bridge function like an ADSL bridge modem does. I have read online how one can configure dhcp on F4 on the router, see the host entry in the home network on the RG web admin page, and then change the RG firewall setting for that host to DMZplus mode. Supposedly this configures a pass-through situation where, via dhcp, the RG gives the public IP to the router and passes through all traffic through to that router. It is supoposed to let someone user their own router or firewall and bypass such on the RG. Unfortunately I cannot get it to work.
Indeed I can see a host entry for the 871 router on the home network page of the RG website. But no matter what I do I cannot get the RG to send the router a DHCP offer or lease. I debugged dhcp and see the router sending a request but nothing is seen from the RG in return. The RG works fine as a dhcp server for everything else on my network when I try it. The 871 router is the only device that will not pull an address via dhcp from the RG.
Any ideas why this is happening. I have connected to various internet service providers with this router and have never had an issue receicing and address on F4 via dhcp.
One interesting happening was that intitially when I started setting this up, I tried to browse to an internet web server and the RG intercepted it and returned a page stating that it detected a router-behind-a-router. It asked me whether to ignore this or to "fix it". First time I selected "fix" and from that moment on I could browse nothing I tried over HTTP except for opendns.com. other types of traffic worked but not http. All browsing attempts were responded to with a site FQDN indicating it was the RG device responding. For a while I could not get the router-behind-a-router web page to show up but finally did. This time I selected "ignore" and internet access has been fine since...but I cannot use the 871 router.
Anyone know the trick to using an 871router with a U-verse resiential gateway?