QinQ Traffic Forwarding Fails Because the Interface Does Not Transparently Transmit the Outer VLAN ID

Fault Symptom

After selective QinQ is configured on an interface, traffic forwarding fails.

Procedure

1. Run the display this command in the view of the interface with selective QinQ configured to check the outer VLAN ID.
2. Run the display vlan vlan-id command in any view to check whether the interface with selective QinQ configured has been added to the outer VLAN. vlan-id specifies the outer VLAN ID.

   <HUAWEI> display vlan 3
   --------------------------------------------------------------------------------
   U: Up;         D: Down;         TG: Tagged;         UT: Untagged;               
   MP: Vlan-mapping;               ST: Vlan-stacking;                              
   #: ProtocolTransparent-vlan;    *: Management-vlan;                             
   --------------------------------------------------------------------------------
                                                                                   
   VID  Type    Ports                                                              
   --------------------------------------------------------------------------------
   3    common  UT:GE0/0/2(U)                                                      
                                                                                   
   VID  Status  Property      MAC-LRN Statistics Description                       
   --------------------------------------------------------------------------------
   3    enable  default       enable  disable    VLAN 0003 

   • If the system displays the message "Error:The VLAN does not exist.", the outer VLAN is not created. Run the vlan batch command to create the outer VLAN and run the display vlan vlan-id command to check whether the interface has been added to the VLAN.
   • If there is no interface with selective QinQ configured, run the port hybrid untagged vlan vlan-id command to add the interface to the VLAN in untagged mode.
   • If the command output does not display the interface with selective QinQ configured but the flag before the interface is not UT, run the port hybrid untagged vlan vlan-id command to add the interface to the VLAN in untagged mode.
   • If the command output displays the interface with selective QinQ configured and the interface has been added to the VLAN in untagged mode, continue to check for other common misconfigurations.