The EAP packet in 802.1x authentication is a bridge protocol data unit (BPDU). By default, Huawei switches do not perform Layer 2 forwarding for BPDUs. If a Layer switch still exists between the 802.1x-enabled device and a user, Layer 2 transparent transmission must be configured on the switch. Otherwise, the EAP packet sent by the user cannot reach the authentication device and the user cannot pass authentication.

Figure 1 Configuring Layer 2 transparent transmission of 802.1x authentication packets

As shown in Figure 1, there is the Layer 2 LAN Switch between the user and device Switch enabled with 802.1x authentication. To ensure that the user's 802.1x authentication packet can reach the Switch through the LAN Switch, perform the following configurations on the LAN Switch (using the S5700HI as an example of the Layer 2 switch).

<HUAWEI> system-view
[HUAWEI] sysname LAN Switch
[LAN Switch] l2protocol-tunnel user-defined-protocol dot1x protocol-mac 0180-c200-0003 group-mac 0100-0000-0002   //group-mac cannot be set to the reserved multicast MAC addresses (from 0180-C200-0000 to 0180-C200-002F) and some other special MAC addresses.
[LAN Switch] interface gigabitethernet 0/0/1 //Connect the Layer 2 switch to the uplink network and configure all interfaces of the users.
[LAN Switch-GigabitEthernet0/0/1] l2protocol-tunnel user-defined-protocol dot1x enable
[LAN Switch-GigabitEthernet0/0/1] bpdu enable
[LAN Switch-GigabitEthernet0/0/1] quit
[LAN Switch] interface gigabitethernet 0/0/2
[LAN Switch-GigabitEthernet0/0/2] l2protocol-tunnel user-defined-protocol dot1x enable
[LAN Switch-GigabitEthernet0/0/2] bpdu enable
[LAN Switch-GigabitEthernet0/0/2] quit
[LAN Switch] interface gigabitethernet 0/0/3
[LAN Switch-GigabitEthernet0/0/3] l2protocol-tunnel user-defined-protocol dot1x enable
[LAN Switch-GigabitEthernet0/0/3] bpdu enable
[LAN Switch-GigabitEthernet0/0/3] quit

More Information: S Series Switches Common Operation Guide