Title

The Cisco switch must have Storm Control configured on all host-facing switchports. (Cat III impact)

Discussion

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.

Check Content

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.

Fix Text

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.

Additional Identifiers

Rule ID: SV-220662r648766_rule

Vulnerability ID: V-220662

Group Title: SRG-NET-000512-L2S-000001

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.