Configuring Storm Control; Understanding Storm Control - Cisco Catalyst 3750-X Software Configuration Manual

Configuring Port-Based Traffic Control
This chapter describes how to configure the port-based traffic control features on the Catalyst 3750-X
or 3560-X switch. Unless otherwise noted, the term switch refers to a Catalyst 3750-X or 3560-X
standalone switch and to a Catalyst 3750-X switch stack.
For complete syntax and usage information for the commands used in this chapter, see the command
Note
reference for this release.
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Configuring Storm Control

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Understanding Storm Control

Storm control prevents traffic on a LAN from being disrupted by a broadcast, multicast, or unicast storm
on one of the physical interfaces. A LAN storm occurs when packets flood the LAN, creating excessive
traffic and degrading network performance. Errors in the protocol-stack implementation, mistakes in
network configurations, or users issuing a denial-of-service attack can cause a storm.
Storm control (or traffic suppression) monitors packets passing from an interface to the switching bus
and determines if the packet is unicast, multicast, or broadcast. The switch counts the number of packets
of a specified type received within the 1-second time interval and compares the measurement with a
predefined suppression-level threshold.
OL-21521-01
Configuring Storm Control, page 28-1
Configuring Protected Ports, page 28-6
Configuring Port Blocking, page 28-7
Configuring Port Security, page 28-8
Displaying Port-Based Traffic Control Settings, page 28-19
Understanding Storm Control, page 28-1
Default Storm Control Configuration, page 28-3
Configuring Storm Control and Threshold Levels, page 28-3
Default Protected Port Configuration, page 28-6
C H A P T E R
Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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