Having problems with an existing DD-WRT (192.168.1.1 wired to an Asus RT-N66U router on 192.168.0.2. They are connected via a
CAT5e cable from the DD-WRT's LAN port to the Asus WAN port.

Asus: IP: 192.168.0.2 / Subnet 255.255.255.0 / Gateway 192.168.1.1 / DNS are the same as programmed on the DD-WRT. The Asus is configured in the Wireless router mode.

DD-WRT: IP 192.168.1.1 / Subnet 255.255.255.0 / Gateway is the proper IP as assigned by ISP.

I can connect via wireless to the Asus, however, cannot connect to Internet. Also, unable to ping to 192.168.1.1 from the Asus.

When I change the Asus routers mode to AP and let the router configure itself I can connect to the Internet, however, the router changes to 192.168.1.2 rather than 192.168.0.2. I want to separate the two subnets because I have an IP system on .1.

Dont know what I'm missing. Any help would be greatly appreciated. Thanks

Change the dd-wrt's subnet mask to 255.255.0.0

That should allow them to talk.

Can't stress enough how important it is to understand subnetting.

What are you trying to accomplish with that setup, commtel?

Could setup Asus
WAN 192.168.1.2
MASK 255.255.255.0
GW 192.168.1.1

ASUS LAN 192.168.0.1

That should separate the LAN segments (more or less). The PCs behind the Asus could still connect to a PC on 192.168.0.X, but not the other way around.