Description Configure a group of tagged Ethernet interfaces for forwarding Bridge Protocol Data Units (BPDUs). BPDU forwarding groups enable you to use the ACOS device in a network that runs Spanning Tree Protocol (STP).
A BPDU forwarding group is a set of tagged Ethernet interfaces that will accept and broadcast STP BPDUs among themselves. When an interface in a BPDU forwarding group receives an STP BPDU (a packet addressed to MAC address 01-80-C2-00-00-00), the interface broadcasts the BPDU to all the other interfaces in the group.
Syntax [no] bpdu-fwd-group group-num
Replace group-num with the BPDU forwarding group number (1-8).
If the ACOS device is a member of an aVCS virtual chassis, specify the group number as follows: DeviceID/group-num
This command changes the CLI to the configuration level for the BPDU forwarding group, where the following command is available.
[no] ethernet portnum [to portnum] [ethernet portnum]
This command enables you to specify the ethernet interfaces you want to add to the BPDU forwarding group.
Mode Configuration mode
Usage This command is specifically for configuring VLAN-tagged interfaces to accept and forward BPDUs.
Rules for trunk interfaces:
• BPDUs are broadcast only to the lead interface in the trunk.
• If a BPDU is received on an Ethernet interface that belongs to a trunk, the BPDU is not broadcast to any other members of the same trunk.
Example The following commands create BPDU forwarding group 1 containing Ethernet ports 1-3, and verify the configuration:
BPDU forward Group 1 members: ethernet 1 to 3