We have a business connection with our ISP. They give us two IP addresses, both dynamically assigned via DHCP, with the option of reserving them and thus getting a static IP address. Right now I have the cablemodem connected to one of the ethernet ports on an RB751U.
How can I make the router request two addresses over the same physical interface? I tried creating a bridge, changing the MAC of the bridge, and assigning it to the physical ethernet port. Then add DHCP to bot the physical interface and the bridge, but it didn’t quite work.
My idea is to have a static address for our services (VPN basically), and another, dynamic address for outgoing traffic (web, email).
You can’t have 2 dhcp clients on the same interface. You need to use 2 interfaces on the router, each with a dhcp client… then connect both router interfaces to the cable modem. (Use a network switch if your cable modem only has 1 interface available).