Creating VLAN Interface FreeBSD

Configuring an Untagged Port

ifconfig (interface_name) inet (ip_address)/(subnet_mask)

Configuring a Tagged Port (VLAN Interface)

ifconfig vlan(vlan_interface_number) create
ifconfig vlan(vlan_interface_number) vlan (vlan_tag_#) vlandev (interface_name)
ifconfig vlan(vlan_interface_number) inet (ip_address)/(subnet_mask)

Deleting the VLAN interface

ifconfig (vlan_interface_number) destroy