Technical data

BLADE OS 5.1 Application Guide
106
 Chapter 7: Quality of Service BMD00136, November 2009
ACL Example 3
Use this configuration to block traffic from a network that is destined for a specific egress port. All
traffic that ingresses port 1 from the network 100.10.1.0/24 and is destined for port 20 is denied.
1. Configure an Access Control List.
2. Add ACL 3 to port 1.
Using Storm Control Filters
The G8000 provides filters that can limit the number of the following packet types transmitted by
switch ports:
 Broadcast packets
 Multicast packets
 Unknown unicast packets (destination lookup failure)
Broadcast Storms
Excessive transmission of broadcast or multicast traffic can result in a broadcast storm.
A broadcast storm can overwhelm your network with constant broadcast or multicast traffic, and
degrade network performance. Common symptoms of a broadcast storm are slow network response
times and network operations timing out.
Unicast packets whose destination MAC address is not in the Forwarding Database are
unknown unicasts. When an unknown unicast is encountered, the switch handles it like a broadcast
packet and floods it to all other ports in the VLAN (broadcast domain). A high rate of unknown
unicast traffic can have the same negative effects as a broadcast storm.
Configuring Storm Control
Configure broadcast filters on each port that requires broadcast storm control. Set a threshold that
defines the total number of broadcast packets transmitted, in Megabits per second.
When the threshold is reached, no more packets of the specified type are transmitted.
>> # access-control list 3 ipv4 source-ip-address 100.10.1.0
255.255.255.0
>> # access-control list 3 egress-port 20
>> # access-control list 3 action deny
>> # interface port 1
>> # access-control list 3