Hello everyone,
Today I will share with you whether BPDUs can pass through the trunk.
Issue Description
Customer using CloudEngine 6800 with next configuration on different ports facing clients:
interface 10GE 1/0/1
port link-type trunk
port trunk pvid vlan 1234
port trunk allow-pass vlan 1 2000 2001 2002 2003
Question: deleting VLAN 1 from allowed VLANs on the trunk link, will the CloudEngine process the received BPDUs or discard them?
Solution
Answer: BPDUs are sent from the switch with source MAC address of the switch
towards a multicast destination (the CE 6800 listening to this address). By default, they do not contain
any VLAN tag, so they are not influenced by the VLAN configurations on the interface.
Deleting VLAN 1 in the allowed VLANs from the trunk using command “[Huawei-GigabitEthernet0/0/1]undo port trunk allow-pass vlan 1” will not make the BPDU packets to be dropped.
That is all I want to share with you! Thank you!
