QinQ

A QinQ VLAN tunnel enables a service provider (SP) to segregate the traffic of different customers in their infrastructure, while still giving the customer a full range of VLANs for their internal use by adding a second 802.1Q VLAN tag to an already tagged frame.

So let us assume for example that an SP exists which needs to offer L2 connectivity to two corporations, “X” and “Y”, that have campuses located in both “A”, “B”. All campuses run Ethernet LANs, and the customers intend to connect through the SP’s L2 VPN network so that their campuses are in the same LAN (L2 network). Hence, it would be desirable for “X”, “Y” to have a single LAN each in both “A”, “B” which could easily exceed the VLAN limit of 4096 of the 802.1Q specification.

QinQ can be enabled on a port or according to predefined conditions.

Warning

C-VLAN is the VLAN tag assigned to the ingress traffic of a QinQ-enabled interface.

Warning

S-VLAN is the VLAN tag assigned to the egress traffic of a QinQ-enabled interface.

  • ACL-mode: Adding and removing S-VLAN is determined by an ACL-dependent action

  • Port-mode: All ingress traffic to a specific QinQ-enabled interface is tagged with an additional VLAN 802.1Q tag (also known as S-VLAN). The S-VLAN ID is equal to that interface’s PVID (access VLAN).
    The S-VLAN tag is added regardless of whether the traffic is tagged or untagged. Traffic coming out from this port, has the S-VLAN stripped from it.

  1. Create the C-VLAN. Run:

    Copy
    Copied!
                

    switch (config) # vlan 200 switch (config vlan 200) # exit

  2. Enter the configuration mode of an Ethernet, LAG, or MLAG interface. Run:

    Copy
    Copied!
                

    switch (config) # interface port-channel 100

  3. Change the switchport mode of the interface to enable QinQ. Run:

    Copy
    Copied!
                

    switch (config interface port-channel 100) # switchport mode dot1q-tunnel

  4. Change its port VLAN ID (PVID). This configures the S-VLAN. Run:

    Copy
    Copied!
                

    switch (config interface port-channel 100) # switchport access vlan 200

  5. Verify the configuration. Run:

    Copy
    Copied!
                

    switch (config interface port-channel 100) # show interface port-channel 100   Po100 Admin state: Enabled Operational state: Up Description: N\A Mac address: 00:00:00:00:00:00 MTU: 1500 bytes(Maximum packet size 1522 bytes) lacp-individual mode: Disabled Flow-control: receive off send off Actual speed: 1 X 40 Gbps Width reduction mode: disabled Switchport mode: dot1q-tunnel QoS mode: uniform MAC learning mode: Enabled Last clearing of "show interface" counters : Never 60 seconds ingress rate: 0 bits/sec, 0 bytes/sec, 0 packets/sec 60 seconds egress rate: 0 bits/sec, 0 bytes/sec, 0 packets/sec   Rx 0 packets 0 unicast packets 0 multicast packets 0 broadcast packets 0 bytes 0 error packets 0 discard packets   Tx 0 packets 0 unicast packets 0 multicast packets 0 broadcast packets 0 bytes 0 discard packets

  6. Verify the configuration. Run:

    Copy
    Copied!
                

    switch (config interface port-channel 100) # show interfaces switchport Interface Mode Access vlan Allowed vlans ------------------------------------------------------------------------- Eth1/1 access 1 Eth1/2 access 1 Eth1/3 access 1 Eth1/4 access 1 Eth1/5 access 1 Eth1/6 access 1 ... Eth1/27 access 1 Eth1/33 access 1 Eth1/34 access 1 Eth1/35 access 1 Eth1/36 access 1 Po400 dot1q-tunnel 200

switchport dot1q-tunnel qos-mode

switchport dot1q-tunnel qos-mode {pipe | uniform}
no switchport dot1q-tunnel qos-mode

Assigns QoS to the service provider’s traffic.
The no form of the command resets the parameter value to its default.

Syntax Description

pipe

Gives the service provider’s traffic the same QoS as the customer’s traffic

uniform

Gives the service provider’s traffic QoS 0

Default

pipe

Configuration Mode

config interface ethernet
config interface port-channel
config interface mlag-port-channel

History

3.4.3000

Example

switch (config interface ethernet 1/1) # switchport dot1q-tunnel qos-mode uniform

Related Commands

show vlan
show interfaces switchport
switchport access vlan
switchport [trunk | hybrid] allowed-vlan
vlan

Notes

© Copyright 2023, NVIDIA. Last updated on Sep 8, 2023.