QinQ 802.1Q in 802.1ad

QinQ (802.1ad) allows multiple VLAN tags to be inserted into a single frame, and can be configured on supported FortiGate devices.

In this example, the customer connects to a provider that uses 802.1ad double-tagging to separate their customer VLANs. The FortiGate connecting to the provider double-tags its frames with an outer provider-tag (S-Tag) and an inner customer-tag (C-Tag).

The customer identifies itself with the provider-tag (S-Tag) 232 and uses the customer-tag (C-Tag) 444 for traffic to its VLAN.

To configure the interfaces:

1. Configure the interface to the provider that uses the outer tag (S-Tag):

   config system interface
       edit "vlan-8021ad"
           set vdom "root"
           set vlan-protocol 8021ad
           set device-identification enable
           set role lan
           set snmp-index 47
           set interface "PORT"  
           set vlanid 232
       next
   end

2. Configure a dynamic VLAN interface that uses the inner tag (C-Tag):

   config system interface
       edit "DVLAN"
           set vdom "vdom1"
           set device-identification enable
           set role lan
           set snmp-index 48
           set interface "vlan-8021ad"
           set vlanid 444
       next
   end