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Catalyst 2960 and 2960-S Switch Software Configuration Guide
OL-8603-09
Chapter 23 Configuring Port-Based Traffic Control
Configuring Storm Control
To disable storm control, use the no storm-control {broadcast | multicast | unicast} level interface
configuration command.
This example shows how to enable unicast storm control on a port with an 87-percent rising suppression
level and a 65-percent falling suppression level:
Switch# configure terminal
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# storm-control unicast level 87 65
This example shows how to enable broadcast address storm control on a port to a level of 20 percent.
When the broadcast traffic exceeds the configured level of 20 percent of the total available bandwidth of
the port within the traffic-storm-control interval, the switch drops all broadcast traffic until the end of
the traffic-storm-control interval:
Switch# configure terminal
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# storm-control broadcast level 20
Configuring Small-Frame Arrival Rate
Incoming VLAN-tagged packets smaller than 67 bytes are considered small frames. They are forwarded
by the switch, but they do not cause the switch storm-control counters to increment. In Cisco IOS
Release 12.2(44)SE and later, you can configure a port to be error disabled if small frames arrive at a
specified rate (threshold).
You globally enable the small-frame arrival feature on the switch and then configure the small-frame
threshold for packets on each interface. Packets smaller than the minimum size and arriving at a specified
rate (the threshold) are dropped since the port is error disabled.
If the errdisable recovery cause small-frame global configuration command is entered, the port is
re-enabled after a specified time. (You specify the recovery time by using errdisable recovery global
configuration command.)
Beginning in privileged EXEC mode, follow these steps to configure the threshold level for each
interface:
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
errdisable detect cause small-frame Enable the small-frame rate-arrival feature on the switch.
Step 3
errdisable recovery interval interval (Optional) Specify the time to recover from the specified
error-disabled state.
Step 4
errdisable recovery cause small-frame (Optional) Configure the recovery time for error-disabled ports to
be automatically re-enabled after they are error disabled by the
arrival of small frames
Step 5
interface interface-id Enter interface configuration mode, and specify the interface to be
configured.
Step 6
small violation-rate pps Configure the threshold rate for the interface to drop incoming
packets and error disable the port. The range is 1 to 10,000 packets
per second (pps)
Step 7
end Return to privileged EXEC mode.