Fault symptom: Customer created a Vlan interface on the Huawei and attached a Pseudo-Wire to the interface. The Pseudo-Wire comes up between the Cisco and the Huawei but he tried to add that vlan to an interface he gets the error below.
[Huawei2-XGigabitEthernet0/0/24]port trunk allow-pass vlan 5
Info: This operation may take a few seconds. Please wait a moment...
Error: VLAN 5 has been configured with L2VPN, and only one interface can be added.
VLL is an MPLS-based Layer 2 virtual private network (L2VPN) technology to directly transmit Layer 2 data. VLL establishes P2P VPN tunnels for P2P communication. However, P2P service eventually became insufficient to meet user requirements, and in response a point-to-multipoint (P2MP) technology, called Virtual Private LAN Service (VPLS) was developed.
In conclusion, only one physical interface(including eth-trunk interface) can be added to the VLANIF which enables VLL. If you cannot use VPLS instead(since other vendors do not support), you can add a switch between multiple CEs and the (PE) to expand the port capability.