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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 50 Configuring Storm Control Enabling Multicast Storm Control
Enabling Multicast Suppression on Catalyst 4900M, Catalyst 4948E, Supervisor Engine 6-E, and Supervisor Engine 6L-E
Catalyst 4900M, Catalyst 4948E, Supervisor Engine 6-E, and Supervisor Engine 6L-E support
per-interface multicast suppression. This allows you to subject incoming multicast and broadcast traffic
on an interface to suppression.
Note Multicast and broadcast suppression share a common threshold per interface.
Multicast suppression takes effect only if broadcast suppression is enabled.
Disabling broadcast suppression on an interface also disables multicast suppression.
To enable multicast suppression, perform this task:
The following example shows how to enable multicast suppression on ports that have broadcast
suppression already enabled:
Switch# configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Switch(config)# int fa3/1
Switch(config-if)# storm-control broadcast include multicast
Switch(config-if)# end
Switch#
Switch# show storm-control
Interface Filter State Broadcast Multicast Level
--------- ------------- --------- --------- -----
Fi3/1 Forwarding Enabled Enabled 50.00%
Enabling Multicast Suppression on the WS-X4515, WS-X4014, and WS-X4013+ Supervisor Engines
Hardware does not provide support for multicast suppression on the WS-X4515, WS-X4014, and
WS-X4013+ supervisor engines. One consequence of using software-based broadcast suppression on
these modules is that all incoming data packets are dropped. Irrespective of your selecting to configure
broadcast suppression only, multicast packets are filtered as well on stub and blocking gigabit ports. The
non blocking gigabit ports that do provide broadcast suppression in hardware also do not filter multicast
packets.
Command Purpose
Step 1 Switch# configure terminal Enters global configuration mode.
Step 2 Switch(config)# interface interface-id Enters interface configuration mode and enter the port to
configure.
Step 3 Switch(config-if)# storm-control
broadcast include multicast Enables multicast suppression.
Step 4 Switch(config-if)# exit Returns to configuration mode.
Step 5 Switch(config)# end Returns to privileged EXEC mode.
Step 6 Switch# show storm-control Verifies the configuration.