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MSTP BPDUs

From cisco/Understanding MTSP:

The IST is the only spanning-tree instance that sends and receives BPDUs; all of the other spanning-tree instance information is contained in M-records, which are encapsulated within MSTP BPDUs.

My questions:

On which VLAN or by wich way are BPDUs sent?

In the case that Instance 0 has problem all instances have a problem - no BPDUs or there are actualy BPDUs per instance?

Can you then map VLAN1 into onther instance for security reason?

Thanks.

Martin.

1 REPLY
Bronze

Re: MSTP BPDUs

Hi,

the BPDU sent over Instance 0 and not over VLAN 1. Istance 0 and Vlan1 are not the same. Please don't use instance 0 for any VLANs. The recommended configuration is:

Switch(config)# spanning-tree mst configuration

Switch(config-mst)# instance 1 vlan 1-20

Switch(config-mst)# instance 2 vlan 21-40

Switch(config-mst)# name region1

Switch(config-mst)# revision 1

Also you should map VLAN1 to another instance.

regards

Peter

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