3Com 2928 User Guide - Page 118

Figure 1-2 Add storm constrain settings for ports Table 1-1 describes the port storm constrain configuration items. Table 1-1 Port storm constrain configuration items Item Remarks Control Mode Specify the action to be performed when a type of traffic exceeds the corresponding upper threshold. Available options include: z None: Perform no action. z Block: Block the traffic of this type on a port when the type of traffic exceeds the upper threshold. z Shutdown: Shut down the port when a type of traffic exceeds the traffic threshold. The port stops forwarding traffic as a result. Broadcast Threshold Multicast Threshold The storm constrain function, after being enabled, requires a full traffic statistics generating interval (in seconds) to collect traffic data, and analyzes the data in the next interval. Thus, it is normal that a period longer than one traffic statistics generating interval is waited for a control action to happen if you enable the function while the packet storm is present. Nevertheless, the action will be taken within two intervals. Set the broadcast, multicast, and unicast thresholds. z None: Perform no storm constrain for the selected port or ports. z pps: Specify the storm constrain upper threshold and lower threshold in packets per second (pps). Unicast Threshold z On a port, you can set the thresholds for broadcast, multicast, and unicast traffic at the same time. To set storm constrain on a port successfully, you must specify the thresholds for at least a type of traffic. z When the pps option is selected, the upper threshold and lower threshold ranges depend on the interface type, as shown in the pps range description on the page. 1-3