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Unanswered Question
May 28th, 2008
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Currently we have a 4507, with a root id of 32768 the default value "that is in our colo fascility", that is connected via a metro-e ethernet switch to our 3560 99.254 which is configured as our root switch with a root id of 4096, and we have a secondary root 99.253 with a root id of 8192.

What is occuring is that our switch in our colo thinks that the the path with the least cost to get to VLAN 7,9,11,12,99 is our metro e, and not the 4507.

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Overall Rating: 5 (1 ratings)


That is correct - the switch that has the lowest root priority is the root for those vlans.

What you can do is change the priroity for those vlans eg:-

In 99.254

spanning-tree vlan 7,9,11,12,99 priority 28672

In 99.253

spanning-tree vlan 7,9,11,12,99 priority 32768

In 4507

spanning-tree vlan 7,9,11,12,99 priority 20480

This will make switch 4507 the root for vlans 7,9,11,12 & 99 - switch 3560 99.254 will be the root for all other vlans and secondary for vlans 7,9,11,12 99, and 99.253 will be secondary for all over vlans.



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