Inbound Load Balancing without being default gateway

khuon

I have a situation where I'm attempting to host a VIP for inbound load-balancing on a pair of pfSense boxes. They however are not the default gateways for the respective WAN or LAN side networks. See attached drawing.

I have the pool and virtual server set up. I'm passing any-any through all interfaces on the firewall (I suppose I could also just turn off the firewall altogether). There's a CARP interface on both the WAN and LAN sides at .8. The VIP is attached to a separate CARP interface on the WAN side at .17.

I can of course ping the VIP interface and I see firewall states created between the clients and the pfSense pair as well as to the servers on the other side. However, I'm seeing them all sitting in SYN. Packet dumps on either interface seem to confirm that I'm not getting a complete TCP handshake through the pfSense boxes. Can anyone tell me what I'm doing wrong or point me down a path for further investigation?
![Internal LB Concept.jpg](/public/imported_attachments/1/Internal LB Concept.jpg)
![Internal LB Concept.jpg_thumb](/public/imported_attachments/1/Internal LB Concept.jpg_thumb)

gmckinney

Since the pfsense boxes are not the default gateways I would suppose you have the default gateway routers configured to point to the pfsense boxes for to reach the respective networks???

Just a question…

gm...

khuon

I haven't done that because I wanted to avoid sticking in a PBR in the layer2/3 switch. A simple static wouldn't work because I have other networks hanging off that switch which I don't want to route through the pfSense pair. I had assumed that when setting up a load-balanced VIP, the traffic would appear out the LAN side as coming from the pfSense's LAN interface so return traffic should go back through it. This is how BigIP works and I figured the behaviour would have been similar.

khuon

Okay. So I got this working by throwing in a NAT rule.