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Storm Control
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 traffic storm.
Storm protection enables you to limit the number of frames entering the device and to define the
types of frames that are counted towards this limit.
When the rate of Broadcast, Multicast, or Unknown Unicast frames is higher than the user-
defined threshold, frames received beyond the threshold are discarded.
To define Storm Control:
1. Click
Configuration > Security > Storm Control
.
2. Select a port and click
Edit
.
•
Port—Select the port for which storm control is enabled.
•
Storm Control—Select to enable Storm Control.
•
Storm Control Mode—Select one of the modes:
o
Unknown Unicast, Multicast & Broadcast—Counts unknown Unicast,
Broadcast, and Multicast traffic towards the bandwidth threshold.
o
Multicast & Broadcast—Counts Broadcast and Multicast traffic towards
the bandwidth threshold.
o
Broadcast Only—Counts only Broadcast traffic towards the bandwidth
threshold.