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spanning tree bpdu

Hi all, can anyone tell me 2 things, firstly do only the uplinks on a switch send out bpdu's ? secondly if I disabled spanning tree on the uplink ports would the switch not send any bpdu's out thus the switch not participating in spanning tree to the rest of the network ?


Re: spanning tree bpdu

Concept says, by default all switchports are in trunk mode. So if any switch is connectd to a port, it tries to negotiate the trunk & once established, send BPDUs. Thus, all access ports have portfast turned on which denies any BPDUs received on port.

Coming to your point, Yes uplinks will share BPDUs. If ur topology has redundant connections, then you are prone to loops if stp is turned off. However, if ur only concern is to limit the diameter of stp, prefer using "vlan allowed" comand on trunks for stp to limit to specific vlans & thus not flooding entire network.

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