How to redirect two domains to same local server IP with pfSense

Going with what Josh said, only one NIC should come into question when you're running links locally from the pfSense box.

Are you sure that the Realtek 8169s are assigned to your WAN interfaces? If you hit up the console and drop to a shell you can run ifconfig to be sure (the Realtek NICs should be re0 re1, etc.).

Assuming:

pbx -> 192.168.2.0/24 -> pfsense1 -> WAN(site-to-site) <-pfsense2 <- 192.168.1.0/24 <- phones

Here's one way you could do this.

Prep:

• Add route in pfsense1 for 192.168.1.0/24 using either pfsense2 WAN IP or VPN tunnel for gateway.
• Add firewall rule in pfsense1 to allow necessary incoming ports FROM 192.168.1.0/24
• Add route in pfsense2 for 192.168.2.0/24 using either pfsense1 WAN IP or VPN tunnel for gateway.
• Add firewall rule in pfsense2 to allow necessary incoming ports FROM 192.168.2.0/24

Changeover:

• Change config on phones to look for PBX on 192.168.2.160.
• Change config on phones to use pfsense2 as default gateway.
• Change pbx to ip 192.168.2.160.
• Change pbx default gateway to pfsense1.

Keep in mind that you need to know what ports the phones use, and you have to unblock those in the firewalls. Also keep in mind that depending on your hardware you may lose some functionality in the phones when working across VPN tunnels / WAN links. For example, 3com NBX's use multicast for time updates, status lights, and paging. Some hardware will simply not support multicast forwarding across a VPN channel - which means these features won't work on remote phones.

I would recommend setting up some kind of computer at the remote site, and then setting up the configs in the firewalls. Verify site-to-site routing/connectivity before continuing with the phones.