3Com 4500G Family Configuration Manual page 47

and takes corresponding actions (that is, blocking or shutting down the port and sending trap messages
and logs) when the traffic detected exceeds the threshold.
Alternatively, you can configure the storm suppression function to control a specific type of traffic. As
the function and the storm constrain function are mutually exclusive, do not enable them at the same
time on an Ethernet port. For example, with broadcast storm suppression ratio set on an Ethernet port,
do not enable the storm constrain function for broadcast traffic on the port. Refer to
Suppression for information about the storm suppression function.
With the storm constrain function enabled on an Ethernet port, you can specify the system to act as
follows when the traffic detected exceeds the threshold.
Blocking the port. In this case, the port is blocked and thus stops forwarding the traffic of this type
till the traffic detected is lower than the threshold. Note that a port blocked by the storm constrain
function can still forward other types of traffic and monitor the blocked traffic.
Shutting down the port. In this case, the port is shut down and stops forwarding all types of traffic.
Ports shut down by the storm constrain function can only be brought up by using the undo
shutdown command or disabling the storm constrain function.
Follow these steps to configure the storm constrain function on an Ethernet port:
To do...
Enter system view
Set the interval for generating
traffic statistics
Enter Ethernet port view
Enable the storm constrain
function and set the lower
threshold and the upper
threshold
Set the action to be taken when
the traffic exceeds the upper
threshold
Specify to send trap messages
when the traffic detected
exceeds the upper threshold or
drops down below the lower
threshold from a point higher
than the upper threshold
Use the command...
system-view
storm-constrain interval
seconds
interface interface-type
interface-number
storm-constrain { broadcast |
multicast } { pps | kbps |
ratio } max-pps-values
min-pps-values
storm-constrain control
{ block | shutdown }
storm-constrain enable trap
1-10
Configuring Storm
Remarks
—
Optional
10 seconds by default
—
Required
Disabled by default
Optional
Disabled by default
Optional
By default, the system sends
trap messages when the traffic
detected exceeds the upper
threshold or drops down below
the lower threshold from a point
higher than the upper
threshold.