The Cisco switch must have Storm Control configured on all host-facing switchports.

A traffic storm occurs when packets flood a LAN, creating excessive traffic and degrading network performance. Traffic storm control prevents network disruption by suppressing ingress traffic when the number of packets reaches a configured threshold levels. Traffic storm control monitors ingress traffic levels on a port and drops traffic when the number of packets reaches the configured threshold level during any one-second interval.

Review the switch configuration to verify that storm control is enabled on all host-facing interfaces as shown in the example below:

interface GigabitEthernet0/3 switchport access vlan 12 storm-control unicast level bps 62000000 storm-control broadcast level bps 20000000

Note: Bandwidth percentage thresholds (via level parameter) can be used in lieu of PPS rate.

If storm control is not enabled at a minimum for broadcast traffic, this is a finding.

Configure storm control for each host-facing interface as shown in the example below:

SW1(config)#int range g0/2 - 8 SW1(config-if-range)#storm-control unicast bps 62000000 SW1(config-if-range)#storm-control broadcast level bps 20000000

Note: The acceptable range is 10000000 -1000000000 for a gigabit Ethernet interface, and 100000000-10000000000 for a ten gigabit interface. Storm control is not supported on most FastEthernet interfaces.