We have now covered the steps that are absolutely necessary for the initial VLAN configuration, but there are some additional features worth mentioning. pfSense supports QinQ tagging; you can configure QinQ by clicking on the QinQs tab on the (assign) page. This will take you to a table showing all the interfaces that have been configured for QinQ. You can add another QinQ interface by clicking on the Add button.
The first option on the QinQ configuration page is the Parent Interface drop-down box. As with VLAN configuration, the parent interface should be an interface that is not being used as an interface on pfSense (in other words, an interface that is being used solely as a parent interface for VLANs). The next option is First level ...
