Created on 08-31-2018 05:43 PM Edited on 11-24-2021 01:09 AM By Anthony_E
Description
This article describes how to process non-tagged packets on a transparent unit. When sending NON-Tagged packets from a Switch to a FortiGate unit in transparent mode, packets are dropped unless the receiving interface is a physical one.
Solution
On FortiGate units, the physical interfaces are the only ones able to process (send and accept) non-tagged packets.
Non-Tagged packets (like VTP, CDP, ...) should never be directed to a non-physical interface, like a VLAN sub-interface. Also "stpforward" must be applied on the port configuration.