- When the default CPCAR value is used, the device transparently transmits a maximum of 10 Layer 2 protocol packets per second. Excess packets are discarded.
- On the S5700HI, if the VLANIF interface configured based on a PVID is bound to a VSI, interfaces corresponding to this PVID cannot forward Layer 2 protocol BPDUs.
- In V200R005 and later versions, when PVST packets need to be transparently transmitted, disable VBST on the interface. Otherwise, PVST packets cannot be transparently transmitted.
- Do not replace the destination MAC addresses of SSTP, STP, GVRP, and GMRP packets with the same multicast MAC address.
When configuring Layer 2 protocol transparent transmission, do not use any of the following multicast MAC addresses to replace the destination MAC address of Layer 2 protocol packets:
- Destination MAC addresses of BPDUs: 0180-C200-0000 to 0180-C200-002F
- Destination MAC address of Smart Link packets: 010F-E200-0004
- Special multicast MAC addresses: 0100-0CCC-CCCC and 0100-0CCC-CCCD
- Common multicast MAC addresses that have been used on the device
- To transparently transmit BPDUs such as DLDP and EFM packets on a physical interface, the L2PT tunnel egress cannot be the Eth-Trunk. Otherwise, BPDU negotiation may be abnormal.
- When an interface is enabled to transparently transmit the packets of a certain protocol, these packets do not participate in protocol processing. For example, after an interface is enabled to transparently transmit STP packets, the interface does not participate in STP calculation. Therefore, you are advised not to enable a protocol and the transparent transmission of this protocol on the same interface.