For this scenario it is required to configure the QinQ stacking sub-interface to access an Layer 2 virtual private network (L2VPN). This configuration allows a physical interface to provide access services for multiple users.
This implementation, however, faces a problem that one physical interface cannot provide L2VPN access to multiple users. To address this problem, you can configure a QinQ stacking sub-interface and bind it to a VSI or L2VC to provide L2VPN access to multiple users.