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Spanning Tree

Spanning tree selects the route bridge by looking at the Priority and the Mac address?

Spanning tree also looks at the Priority of a port and Mac address to select the Root port, blocked port etc.

Where does the port cost come into it?

10meg = 100, 100 meg = 19, 1 gps = 4, 10 gps =2

Thanks.

Mike.

1 ACCEPTED SOLUTION

Accepted Solutions
Silver

Re: Spanning Tree

Answer to first question is true...root bridge is selected by priority. If priority for two switches are the same then MAC is used. Lower the value of priority/MAC, the better.

Port cost comes into picture when closest path to the root bridge has to be decided.

The valeus you have indicated are default port costs.

Thanks.

1 REPLY
Silver

Re: Spanning Tree

Answer to first question is true...root bridge is selected by priority. If priority for two switches are the same then MAC is used. Lower the value of priority/MAC, the better.

Port cost comes into picture when closest path to the root bridge has to be decided.

The valeus you have indicated are default port costs.

Thanks.

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