1-11 Storm Constrain ConfigurationOverviewThe storm constrain function limits traffic of a port within a predefined upper threshold to suppresspacket storms in an Ethernet. With this function enabled on a port, the system detects the amount ofbroadcast traffic, multicast traffic, and unicast traffic reaching the port periodically. When a type of trafficexceeds the threshold for it, the function, as configured, blocks or shuts down the port, and optionally,sends trap messages and logs.Alternatively, you can configure the storm suppression function to control a specific type of traffic. Asthe storm suppression function and the storm constrain function are mutually exclusive, do not enablethem at the same time on an Ethernet port. For example, with broadcast storm suppression enabled ona port, do not enable storm constrain for broadcast traffic on the port. The storm suppression function isconfigured in Device > Port Management. For details, refer to Port Management.With storm constrain enabled on a port, you can specify the system to act as follows when a certain typeof traffic (broadcast, multicast, or unicast) exceeds the corresponding upper threshold:z Block: Block the port. In this case, the port is blocked and thus stops forwarding the traffic of thistype until the type of traffic drops down below the lower threshold. Note that a port blocked by thestorm constrain function can still forward other types of traffic and collect statistics for the blockedtraffic.z Shutdown: Shut down the port. In this case, the port is shut down and stops forwarding all types oftraffic. To bring up the port, select Device > Port Management to configure the port, or cancel thestorm constrain setting on the port.Configuring Storm ConstrainSetting the Traffic Statistics Generating IntervalSelect Device > Storm Constrain from the navigation tree to enter the page shown in Figure 1-1. In theInterval for generating traffic statistics text box, input the traffic statistics generating interval forstorm constrain.
