Traffic Control Commands - D-Link xStack DES-3528 Series Cli Reference Manual

xStack® DES-3528/DES-3552 Series Layer 2 Fast Ethernet Managed Switch CLI Reference Guide
T C
RAFFIC ONTROL
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 will monitor and control the situation.
The packet storm is monitored 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 overflow 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.
The Switch will also 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 the packet storm discontinues before the countdown timer expires, the port will
again allow all incoming traffic. 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, if we have set the
trap field. Once in Shutdown Forever mode, the port will be recovered automatically, when the auto-recover time has
expired. (If the value was set to "0", the port will not be auto recovered), or the user manually resets the port using the
config ports enable command, mentioned previously in this manual.
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
log state
config traffic control
auto_recover_time
show traffic control
config traffic trap
Each command is listed, in detail, in the following sections.
config traffic control
Purpose
Syntax
Description
Parameters
C
OMMANDS
Parameters
[<portlist> | all] {broadcast [enable | disable] | multicast [enable | disable] | unicast [enable |
disable] | action [drop | shutdown] | threshold <value 0-255000> | countdown [<min 0> |
<min 3-30> | disable] | time_interval <sec 5-600>}
[enable | disable]
[<min 0> | <min 1-65535>]
{[<portlist>]}
[none | storm_occurred | storm_cleared | both]
Used to configure broadcast/multicast/unicast 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 [enable | disable] | multicast [enable |
disable] | unicast [enable | disable] | action [drop | shutdown] | threshold <value 0-
255000> | countdown [<min 0> | <min 3-30> | disable] | time_interval <sec 5-600>}
This command is used to configure broadcast/multicast/unicast storm control. By adding the
new software traffic control mechanism, the user can now use both a hardware and software
mechanism, the latter of which will now provide shutdown, recovery and trap notification
functions for the Switch.
<portlist> − Used to specify a group list of ports to be configured for traffic control, as defined
below:
all − Specifies all portlists are to be configured for traffic control on the Switch.
broadcast [enable | disable] − Enables or disables broadcast storm control.
multicast [enable | disable] − Enables or disables multicast storm control.
unicast [enable | disable] − Enables or disables unicast traffic control.
action – Used to configure the action taken when a storm control has been detected on the
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