Defining Storm Control - Cisco SF 300-08 Administration Manual

Configuring Security

Defining Storm Control

STEP 3
Defining Storm Control
STEP 1
STEP 2
STEP 3
Cisco Small Business 300 Series Managed Switch Administration Guide
• Local IP Address—Local IP address through which the switch is offering the
service.
• Local Port—Local UDP port through which the switch is offering the service.
• Application Instance—The service instance of the UDP service. (For
example, when two senders send to the same destination.)
Click Apply. The services are added, and the switch is updated.
When Broadcast, Multicast, or Unknown Unicast frames are received, they are
duplicated, and a copy is sent to all possible egress ports. This means that in
practice they are sent to all ports belonging to the relevant VLAN. In this way, one
ingress frame is turned into many, creating the potential for a storm.
Storm protection enables you to limit the number of frames entering the switch
and to define the types of frames that are counted towards this limit.
When a threshold (limit) is entered in the system, the port discards traffic after that
threshold is reached. The port remains blocked until the traffic rate drops below
this threshold. It then resumes normal forwarding.
To define Storm Control:
Click Security > Storm Control. The Storm Control Page displays.
This page displays storm control parameters for all ports.
All the fields on this page are described in the Edit Storm Control Page except for
the Storm Control Rate Threshold (%). It displays the percent of the total
available bandwidth for unknown unicast, multicast, and Broadcast packets before
storm control is applied at the port. The default value is 10% of the maximum rate
of the port and is set in the Edit Storm Control Page.
Select a port and click Edit. The Edit Storm Control Page displays.
Enter the parameters.
• Port—Select the port for which storm control is enabled.
• Storm Control—Select to enable Storm Control.
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