3Com 4210G Series Configuration Manual page 192

It is required that, after the configuration, CE 1 and CE 2 implement consistent spanning tree
calculation across the service provider network, and that the destination multicast MAC address
carried in BPDUs be 0x0100-0CCD-CDD0.
Figure 11-3 Network diagram for configuring BPDU tunneling for STP
Configuration procedure
1) Configuration on PE 1
# Configure the destination multicast MAC address for BPDUs as 0x0100-0CCD-CDD0.
<PE1> system-view
[PE1] bpdu-tunnel tunnel-dmac 0100-0ccd-cdd0
# Create VLAN 2 and assign GigabitEthernet 1/0/1 to VLAN 2.
[PE1] vlan 2
[PE1-vlan2] quit
[PE1] interface gigabitethernet 1/0/1
[PE1-GigabitEthernet1/0/1] port access vlan 2
# Disable STP on GigabitEthernet 1/0/1, and then enable BPDU tunneling for STP on it.
[PE1-GigabitEthernet1/0/1] undo stp enable
[PE1-GigabitEthernet1/0/1] bpdu-tunnel dot1q stp
2) Configuration on PE 2
# Configure the destination multicast MAC address for BPDUs as 0x0100-0CCD-CDD0.
<PE2> system-view
[PE2] bpdu-tunnel tunnel-dmac 0100-0ccd-cdd0
# Create VLAN 2 and assign GigabitEthernet 1/0/2 to VLAN 2.
[PE2] vlan 2
[PE2-vlan2] quit
[PE2] interface gigabitethernet 1/0/2
[PE2-GigabitEthernet1/0/2] port access vlan 2
# Disable STP on GigabitEthernet 1/0/2, and then enable BPDU tunneling for STP on it.
[PE2-GigabitEthernet1/0/2] undo stp enable
[PE2-GigabitEthernet1/0/2] bpdu-tunnel dot1q stp
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