IP Networking

Hello,

I'm attempting to setup a test network with a client-server based architecture using a proprietary application. The client works by communicating with the server on separate links (typically cellular connections) and then initiates a tunnel over each active link. However, in place of the cellular links, i'm using three Ethernet links segmented by VLANS. Each link has its own gateway which all reside on the same intermediate server which is running FREEBSD and has two NICs. This will act as the router. The reason for this is so that I can use dummynet to apply varying propagation and queuing delays to each link based on source IP and VLAN on this router. What I'm struggling with is the setup of this router. I can't seem to get the NICs to forward packets to each other even though IPv4 forwarding is enabled. I can ping the server from the NIC (re0) to which the NIC is connected, and the client from the other NIC (re1). I cant however ping across them i.e. re1 to server. I'm not sure what the right approach is here and was hoping for some guidance as i'm no expert. My ipfw rules are set to allow all.

See attached for setup.

Thanks.