How to connect 2 routers LAN-WAN and create subnet?


Sep 8, 2012
Hey everyone

I'm trying to connect two routers and create a subnet but failing due to a little knowledge but no real understanding! :pfff:

I've read the ultimate setup thread loads of times but can't get my setup to work. Can someone please help?

Here's the setup I'm trying to build:

Internet -> Master ADSL modem/router (No NAT, no DHCP) -> Slave cable router (NAT, DHCP)

I want to connect 3 Xboxes to the master router with external IPs to avoid the whole "moderate/strict" NAT nightmare. Then I'll connect everything else (PCs, Macs, wireless devices etc) to the Slave router which will assign IP addresses and do the NAT thing. Both routers are Netgear N150s (master is ADSL, slave is Cable).

Here's what I've tried so far:

Master router:

All IP addresses supplied by ISP

Internet IP: xxx.68.160.143
DNS: and
Router IP: xxx.68.160.142
Subnet mask:
Gateway: xxx.68.160.143
DHCP disabled - all connected devices are given external IPs in range xxx.68.160.137 - xxx.68.160.141
NAT disabled

Slave router:

WAN port on slave connected to LAN port on master

Internet IP: xxx.68.160.??? (should this be the 142 address of the master router?)
DNS: and (or the address of the master router?)
Router IP: xxx.68.160.137 (one of the external IPs?)
Subnet mask: (is this right?)
Gateway: xxx.68.160.??? (should this be the 142 address of the master router?)
DHCP enabled: but issuing IPs in what range?
NAT enabled

Anyone who can solve this will be rated 'network genius'! :D





So your ISP gives you five static external IP addresses and you will use three for XBOX connections and one for the rest of your network, correct? You actually could just use a switch in place of the "master" router since that is all that it is doing.

In that case the external IP address for the "slave" router would be one of your five ISP issue addresses. And the "slave" router could use an internal address range.

If you keep the "master" router in place you should configure the WAN port of the "slave" router to a gateway IP that is the address of the "master" router. The "slave" router can then use an internal range, like for the "slave" router and its DHCP will assign in the range to .254 with a subnet of The "slave" DNS will also be the master gateway. Your internal devices will automatically obtain an IP address from the "slave" router, your only actual router, which will be in the 192.168.1.x range.