We currently have a L3 switch with different networks A, B, C & D. Network A (Finance), B (Engineering), C(Boss) are where all PCs are located and they access the server network D.
Right now, our bosses wants to put a firewall in between so that it restricts the access to server in Network D (Servers).
Network B -> Firewall -> Network D
The layer 3 switch also performs routing functions routing traffic between A, B, C & D.
I was wondering how does VRF apply in this situation. Each VLAN has an IP on their interface.
Gateways of each network
Network A - 192.168.1.253
Network B - 192.168.2.253
Network C - 192.168.3.253
Network D - 192.168.4.253
Problem here is that if I were to set my firewall to have an IP of 192.168.4.253. What are the things I need to do for traffic directed to servers to flow through the firewall first before going to the servers. Is VRF needed in this case?
VRFs are not needed in your case.
you just need to put the network D behind the firewall so that a static route pointing to FW outside is used to reach Network D
Net B -- L3 switch -- vl. x - FW -- Net D
where vlan x is a new different vlan used to communicate with the FW.
This is in the case of a L3 FW.
You can also use a transparent firewall that can be useful if multicast traffic is involved
Hope to help