Administrator Guide

Security Commands 1058
console(config)#interface range gi1/0/1-24
console(config-if)#storm-control multicast level 20
console(config-if)#storm-control multicast action shutdown
console(config-if)#exit
storm-control unicast
Use the storm-control unicast command in Interface Configuration mode to
enable storm control for an interface. Unicast storm control limits the
number of unicast destination lookup failures (DLFs). Use the no form of the
command to disable unicast storm control or to return the configuration to
the default.
Syntax
storm-control unicast [level level |rate rate|action{shutdown|trap}]
no storm-control unicast [level | rate]
• level— The configured rate as a percentage of link bandwidth (Range: 0-
100)
• rate—The configured rate in packets per second. (Range: 0-14880000)
• action—The configured action: shutdown or trap.
Default Configuration
By default, unicast storm control is not enabled on any interfaces.
The default threshold for unicast traffic is 5% of link bandwidth.
Command Mode
Interface Configuration (Ethernet) mode, Interface Range mode
User Guidelines
A destination lookup failure (DLF) is when a L2 unicast packet is unable to
resolve the destination MAC address to an egress interface (no MAC
forwarding address entry exists). The standard behavior for L2 DLFs is to
flood the packet on all ports in the VLAN other than the port on which the
packet was received. This flooding behavior can cause significant amounts of
bandwidth to be consumed, potentially disrupting the forwarding of other
traffic.