How to set the interface uses only for forwarding on the VM router?

Have a network diagram is shown in the picture:
5e9ab9a108abc093932138.jpeg
Explanation:
  1. "Server1" has 2 network interface "NIC1" and "NIC2".
  2. On Server1 raised "VM1" from virtualbox, which is installed on pfsense is also (a software router\proxy\firewall)
  3. On "VM1" configured with 2 network interface bridge for each physical NIC s Server1.
  4. In NIC1 the cable comes from the ISP with an external IP address
  5. NIC2 is used as a LAN interface and receives settings from pfsense is also on VM1, which raised DNS/DHCP.



What it takes: I need to get on Server1 NIC1 were used ONLY for prokidyvaya traffic to VM1 to ultimately the ability to learn the standard scheme WAN <---> firewall<--->LAN, where Server1 is the host LAN network.
Otherwise I have 2 look out of the node (Server1 and VM1).
How to implement it?
April 19th 20 at 12:40
1 answer
April 19th 20 at 12:42
Get the IP address with the physical nic1. The default gateway for server1, let it be the IP address of the internal virtual interface pfsense is also

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