Spanning Tree Protocol

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Sep 1st, 2003
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I got a cisco switch with all ports configured to a single vlan. If I turn on spanning tree protocol for all ports, and if I connect port 1 to port 2. Will it affect the network that is connected to other ports since there is a loop and hence will create broadcast storm.

The reason I asked this is that all the spanning tree protocol documents are talking about more than 2 switches which a spanning-tree capable. I am talking about a single switch with ports looping.

If spanning-tree cannot block port 1 and port 2, what is the solution to prevent broadcast storm when port 1 and 2 are connected together?

Thanks a lot.


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milan.kulik Mon, 09/01/2003 - 23:26
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if you connect connect port 1 to port 2 on the same switch, STP should block one port (probably port 2 if you leave the deafult values).

But you can create a loop when connecting a hub to port 1 and make a loop connecting together two ports on the hub.

Use STP bpduguard feature ( to prevent broadcast storm in that case.




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