Shulou(Shulou.com)06/03 Report--

Storm control

Broadcast packets have unique characteristics, each device in the broadcast domain will be able to process broadcast packets, if there is excessive broadcast traffic in a network segment, then all devices will be affected.

To mitigate the impact of overbroadcast, catalyst series switches provide broadcast suppression features, and broadcast suppression detection takes the following two behaviors:

1. Discard excess traffic

two。 Disable ports that accept excessive traffic

By monitoring the traffic entering the port during the 1s cycle, if the broadcast traffic exceeds the configured threshold, the switch will take the assigned illegal action.

There are two ways to measure whether desired traffic needs to be suppressed:

1. Broadcast, multicast, and multicast traffic can be monitored separately as a percentage of the total bandwidth available on the port.

two。 The rate at which the interface accepts broadcast, multicast, and unicast packets, that is, how many packets are received per second.

For cisco IOS software-based switches, broadcast suppression is also known as storm control. When using storm control features, the only violation of cisco IOS software-based catalyst 6500 series switches is to discard packets; in cisco IOS software-based catalyst 4500 series switches, in addition to the option to drop packets, the violation also includes the shutdown option.

Various catalyst series switches support broadcast, multicast, and unicast suppression:

Turn on storm control:

Switch (config-if) # storm-control [broadcast | multicast | unicast] level level

Switch (config-if) # storm-control action shutdown

A higher threshold allows more packets to pass through, and setting the threshold to 100% means that no traffic will be restricted. 0% means that all broadcast multicast and unicast traffic will be closed. By default, storm control for unicast multicast broadcasts is turned off on the switch, meaning that the suppression level is 100%.

View the storm suppression level configured on the interface: Switch#show storm-control fastEthernet0/1 [broadcast | multicast | unicast]

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.