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Port costs

Hello.

My back bone presently has a port cost of 2, which connects our two core switches.

The rest of my link currently have a port cost of 4.

The network is set up in such a way that each stack of switches has a link to both core switches.

Now if my backbone with a current cost of 2 was to fail, which of the parths with a port cost of 4 would spanning tree decided to use? The one with the least hops? Everything with a port cost of 4 is connected by gigabit fibre, so the only varible i can see is the amount of hops/switches.

Many thanks.

Mike.

1 REPLY
Silver

Re: Port costs

STP uses the following in order to determine the path:

Lowest Bridge ID

Lowest root path cost

Lowest sender bridge ID

Lowest sender port ID

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