D-Link xStack DES-6500 User Manual - Traffic Control
xStack DES-6500 Modular Layer 3 Chassis Ethernet Switch User Manual
Traffic Control
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 window 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
Storm Control Recover
setting seen in the figure below. To utilize the Software
method of Storm Control, choose the
Shutdown
option of the
Action
field in the window below.
To view the following window to configure Traffic Control, click
Configuration > Traffic Control
.
Figure 6- 37. Traffic Control Settings and Traffic Control Table window
The user may set the following parameters:
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