Problem installing AmpliFi HD router behind AT&T BGW210-700 in Passthrough mode.
Went to 192.168.1.254 and changed settings as follows: in Firewall then IP Passthrough set Allocation to Passthrough in DHCP-Fixed and entered MAC address of AmpliFi router and saved. In Home Network Subnets & DHCP set Server Enable to Off Then set Cascaded Router Enable to On, Cascaded Router address to 0.0.0.0, Network Address of AmpliFi, and Subnet Mask left on 255.255.255.248. Then after clicking save got red error message stating: "Cascaded router network address must be a WAN-side subnet". Need help understanding how to enter this parameter.