Chapter 32 Configuring Broadcast Suppression; Understanding How Broadcast Suppression Works - Cisco WS-X6066-SLB-APC - Content Switching Module Software Manual

Configuring Broadcast Suppression
This chapter describes how to configure broadcast suppression on the Catalyst 6000 family switches.
For complete syntax and usage information for the commands used in this chapter, refer to the
Note
Catalyst 6000 Family Command Reference publication.
This chapter consists of these sections:
•
•

Understanding How Broadcast Suppression Works

Broadcast suppression prevents switched ports on a LAN from being disrupted by a broadcast storm on
one of the ports. A LAN broadcast storm occurs when broadcast or multicast packets flood the LAN,
creating excessive traffic and degrading network performance. Errors in the protocol-stack
implementation or in the network configuration can cause a broadcast storm.
Broadcast suppression uses filtering that measures broadcast activity on a LAN over a one-second time
period and compares the measurement with a predefined threshold. If the threshold is reached, further
broadcast activity is suppressed for the duration of a specified time period. Broadcast suppression is
disabled by default.
Figure 32-1
broadcast suppression occurs between time intervals T1 and T2 and between T4 and T5. During those
time periods, the amount of broadcast traffic exceeded the configured threshold.
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Understanding How Broadcast Suppression Works, page 32-1
Configuring Broadcast Suppression, page 32-2
shows the broadcast traffic patterns on a port over a given period of time. In this example,
Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
C H A P T E R
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