Hello John,

storm-control is an helpful feature in a L2 switched environment.

the benefits are the capabilities to detect and limit the disruptive effects of a broadcast storm caused by a just formed bridging loop for any event.

There can be cases where without storm control you even lost remote access to devices and you cannot fix the problems quickly.

In an healthy network you can have a baseline of the broadcast level in the network.

Other benefits include the ability to provide protection for slower ports that are members of Vlans where multiple devices with high speeds are connected: here it is likely that a FE port can be saturated by traffic that is supported on GE ports.

You can define storm control for :

broadcast

multicast

unknown unicast

with different levels.

The mechanism is efficient and packets over the configured threshold are dropped and counted as output drops.

The main disavantage is that there is no selection:

each traffic type counts for the threshold no ACL can be used to define good multicast for example and unwanted multicast.

We use broadcast storm control with 1% threshold on GE ports without any issues

Hope to help

Giuseppe