Route traffic received on IP alias through OpenVPN tunnel

[linkexplorer]

Greetings,

New pfsense user here.

I have set up an OpenVPN client on a pfsense box and can successfully route traffic to specific destinations through the VPN while letting all other traffic pass through (i.e. not going out via the VPN).

However, I would like to assign an additional IP to the pfsense box and route all traffic received on this IP (from LAN clients using this IP as a gateway) through the VPN.

I have assigned a virtual IP (IP alias) to the LAN interface.

Any pointers on how to set up routing to achieve the above? For simplicity, I prefer to keep all clients on the same subnet.