In virtual inline mode, the router uses policy based routing (PBR) rules to redirect incoming and outgoing WAN traffic to the appliance for acceleration, and the appliance forwards the processed packets back to the router.
Virtual inline mode provides a solution for asymmetric routing issues faced in a deployment with two or more WAN links.
The tasks for configuring virtual inline mode are performed on the router. On the SD-WAN appliance, just verify that the software version supports virtual inline mode and provision the instances with the necessary IP addresses. Do not change the default forwarding method.