Broadcast Storm Control Commands - D-Link TM DES-6500 Cli Manual

xStack DES-6500 Modular Layer 3 Chassis Ethernet Switch CLI Manual
On a computer network, packets such as Multicast packets and Broadcast packets continually flood the network as normal
procedure. At times, this traffic may increase do to a malicious endstation on the network or a malfunctioning device, such as a
faulty network card. Thus, switch throughput problems will arise and consequently affect the overall performance of the switch
network. To help rectify this packet storm, the Switch implements two methods to monitor and control the situation.
1. Hardware: The packet storm is monitored using the Switch's hardware to determine if too many packets are
flooding the network, based on the threshold level provided by the user. Once a packet storm has been detected, the
Switch will drop packets coming into the Switch until the storm has subsided. This method can be utilized by
selecting the drop option of the Action field in the config traffic control command below.
2. Software: The device's software will scan and monitor packets coming into the Switch by monitoring the Switch's
chip counter. This method is only viable for Broadcast and Multicast storms because the chip only has counters for
these two types of packets. Once a storm has been detected (that is, once the packet threshold set below has been
exceeded), the Switch will shutdown the port to all incoming traffic with the exception of STP BPDU packets for a
time period, specified using the countdown field. If this field times out and the packet storm continues, the port will
be placed in a Shutdown Forever mode which will produce a warning message to be sent to the Trap Receiver. Once
in Shutdown Forever mode, the only method of recovering this port is to manually recoup it using the config traffic
control_recover setting seen in the command list below. To utilize the Software method of Storm Control, choose
the shutdown option of the action field in the config traffic control command below.
The broadcast storm control commands in the Command Line Interface (CLI) are listed (along with the appropriate parameters)
in the following table.
Command
config traffic control
config traffic
control_recover
config traffic trap
show traffic control
Each command is listed, in detail, in the following sections.
config traffic control
Purpose
Syntax
Description
B
ROADCAST
Parameters
[<portlist> | all] {broadcast [enabled | disabled] | multicast [enabled
| disabled] | dlf [enabled | disabled] | action [drop | shutdown] |
threshold <value 0-2047> | countdown [<value 0> | <value 5-30>] |
time_interval <value 5-10>}
[<portlist> | all]
[none | storm_occurred | storm_cleared | both]
{<portlist>}
Used to configure broadcast/multicast/dlf packet storm control.
The software mechanism is provided to monitor the traffic rate in
addition to the hardware storm control mechanism previously
provided.
config traffic control [<portlist> | all] {broadcast [enabled |
disabled] | multicast [enabled | disabled] | dlf [enabled |
disabled] | action [drop | shutdown] | threshold <value 0-
2047> | countdown [<value 0> | <value 5-30>] | time_interval
<value 5-10>}
This command is used to configure broadcast/multicast/dlf storm
control. By adding the new software traffic control mechanism, the
user can now use both a hardware and software mechanism, the
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OMMANDS