Chapter 17 Configuring Port-Based Traffic Control; Configuring Storm Control - Cisco Catalyst 2950 Software Configuration Manual

Configuring Port-Based Traffic Control
This chapter describes how to configure the port-based traffic control features on your switch.
For complete syntax and usage information for the commands used in this chapter, refer to the
Note
Catalyst 2950 Desktop Switch Command Reference for this release.
This chapter consists of these sections:
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Configuring Storm Control

A packet storm occurs when a large number of broadcast, unicast, or multicast packets are received on
a port. Forwarding these packets can cause the network to slow down or to time out. Storm control is
configured for the switch as a whole but operates on a per-port basis. By default, storm control is
disabled.
Storm control uses rising and falling thresholds to block and then restore the forwarding of broadcast,
unicast, or multicast packets. You can also set the switch to shut down the port when the rising threshold
is reached.
Storm control uses a bandwidth-based method to measure traffic activity. The thresholds are expressed
as a percentage of the total available bandwidth that can be used by the broadcast, multicast, or unicast
traffic.
The rising threshold is the percentage of total available bandwidth associated with multicast, broadcast,
or unicast traffic before forwarding is blocked. The falling threshold is the percentage of total available
bandwidth below which the switch resumes normal forwarding. In general, the higher the level, the less
effective the protection against broadcast storms.
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Configuring Storm Control, page 17-1
Configuring Protected Ports, page 17-3
Configuring Port Security, page 17-3
Configuring and Enabling Port Security Aging, page 17-6
Displaying Port-Based Traffic Control Settings, page 17-7
C H A P T E R
Catalyst 2950 Desktop Switch Software Configuration Guide
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