PRP handling in NAT mode with virtual wire pair

PRP (Parallel Redundancy Protocol) is supported in NAT mode for a virtual wire pair. This preserves the PRP RCT (redundancy control trailer) while the packet is processed by the FortiGate.

To configure PRP handling on a device in NAT mode:

1. Enable PRP in the VDOM settings:

   (root) # config system settings
       set prp-trailer-action enable
   end

2. Enable PRP in the NPU attributes:

   (global) # config system npu
       set prp-port-in "port15"
       set prp-port-out "port16"
   end

3. Configure the virtual wire pair:

   (root) # config system virtual-wire-pair
       edit "test-vwp-1"
           set member "port15" "port16"
       next
   end