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

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-101191	CISC-L2-000160	SV-110295r1_rule		Low

Description
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.

Description

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.

STIG	Date
Cisco IOS XE Switch L2S Security Technical Implementation Guide	2020-05-20

Details

Check Text ( C-100071r1_chk )
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 bps 62000000 storm-control broadcast 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.

Check Text ( C-100071r1_chk )

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 bps 62000000
storm-control broadcast 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 (F-106895r1_fix)
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 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.

Fix Text (F-106895r1_fix)

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 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.