WAN and LAN with same Network Range

Niklas,

bridging the LAN and WAN1 is not a good option. If your LAN is small, change  the LAN ip netmask, otherwise contact your ISP to have a different IP address. This is something that you could manage before getting the second WAN connection.

Hey there,

I am not planing in bridging the wan and Lan interface. But there are 2 separate nics so if the wan gets an ip via DHCP and the network range is the same then on the Lan interface what happens?

Unless you use bridging, different interfaces cannot fall in the same ip network.

If the firewall rules are bind to the nic I don't see any  problem or am I wrong

Routing comes into play, so you have to change an ip that must be in separated network.