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Switch is 100% spanning tree utilized

I have a Sonet network that has a management vlan and Spaning tree is controleld by the ethernet cards on the Sonet...Cisco spannign tree is disabled on the switches, but this morning I had a storm from a switch..and it is causign havoc on omy network...Why does the Interface of the Vlan participate or respond to these broadcasts...the data ports on the switch pass through, but the management vlan itself is hammered...How is that me it sounds like the sonet network is not doing spanning tree very well...the CPU utilization is 100% and the spanning process is the culprit at 60%

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Re: Switch is 100% spanning tree utilized

Hello Dane,

there is a bridging loop somewhere.

to break the loop disable one interface on Cisco switch side.

I would suggest to reconsider STP configuration on your side:

disabling STP is not usually a good choice.

You can try to make your switches less preferred for that vlan with a very high priority so that they are not elected root bridge

to avoid to feed with excessive broadcast from your side you can implement broadcast storm-control that works outbound

you may ask to the sonet provider if they can implement a similar function

Hope to help


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