Alternatives to storm-control on Cat 6509.

Peter George Peter.George at
Fri Aug 21 05:39:34 CDT 2009


I have several Catalyst 6500 (Supervisor 32) aggregation switches with WS-X6148A-GE-TX and WS-X6148-GE-TX line cards.

These line cards do not support storm-control/broadcast suppression. This impacted us badly during a recent spanning tree event.

As it stands, we are at risk of overwhelming control planes with excess broadcast or multicast traffic, and I need to find alternative ways to protect these switches.

I have been researching STP enhancements, and control-plane policing in the following documents, and would appreciate advice from engineers who may have had to implement similar workarounds for storm-control in a service provider setting.

* Configuring Denial of Service Protection

* Configuring Control Plane Policing

* Configuring Optional STP Features

So, if we can't mitigate against STP events using storm-control or broadcast suppression, what might be the best combination of STP enhancements and control-plane policing?

For example, is it possible to rate-limit broadcast/multicast, STP and ARP on a per VLAN basis? If so, how?

Many thanks,


Peter George
t: 0845 1199 900
d: 0131 514 4022

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