So, I'm trying to set up a buffalo router with dd-wrt loaded stock, If I leave the settings alone, the router loses its default gateway each time, and the router admin back-end is never accessible again. I've tried disabling DHCP, no wan, making it a DHCP forwarder, and giving it a static IP that is free. We already have a DHCP server running which I think is conflicting. One time I gave it a static IP and it seemed to crash all of our network, including phones, momentarily.
The router is a Buffalo WZR-HP-AG300H, with ddwrt, network has DHCP server running that I can't take out of equation, various firewalls, etc.
Any suggestions on purely making this an access point that doesn't lose its gateway?