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DGS-3400 Series Layer 2 Gigabit Ethernet Managed Switch CLI Manual
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RAFFIC
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ONTROL
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OMMANDS
There are two modes used for packet storm control on the Switch, Drop mode and Shutdown mode. Drop mode is
hardware-based (chip-based) and Shutdown mode is a function of software. The two modes are incompatible with each
other, therefore it is necessary to determine which method is best suited to the network environment where it is used.
Drop mode
The Drop mode storm control function is used to configure three chip-based hardware tables for state and a single
threshold value (threshold value is the same for all three tables). If the threshold value is exceeded on a port, the Switch
will drop all packets on the port. In Drop mode, some parameters such as “time interval” and “count down,” as well as the
CLI command, “config traffic control auto_recover_time” are software-based functions and therefore not applicable for
Drop mode traffic control.
Shutdown mode
Shutdown mode is a software-based storm control function. When shutdown mode is used, the state of the hardware
tables used for Drop mode are set to disable. Shutdown mode does not support DLF storm control. All configurations
except the port state are saved in the software table. The CPU receives the port state from the counter table (updated at
2 second intervals). If a counter is exceeded on a port, the CPU is shutdown. All packets, except BPDU packets, on the
port are dropped. If the port remains in shutdown status for a configurable period (the count down value), the port enters
shutdown forever status. The port link is down and remains disabled until either the configurable recover timer is timed
out or the CLI command “config ports [ <portlist> | all ] state enable" is manually entered.
The Traffic Control commands in the Command Line Interface (CLI) are listed (along with the appropriate parameters) in
the following table.
Command
Parameters
config traffic control
[<portlist> | all] {broadcast [enable| disable] | multicast [enable | disable] | [dlf |
unicast ] [enable | disable] | action [ drop | shutdown ] | threshold <value 0-
255000 > | countdown [<min 0> | <min 3-30> | disable] | time_interval <sec 5-
600>}
config traffic trap
[ none | storm_occurred | storm_cleared | both ]
show traffic control
{<portlist>}
config traffic control
auto_recover_time
[<min 0> | <min 1-65535>]
config traffic control_recover
[<portlist> | all]
Each command is listed, in detail, in the following sections.
config traffic control
Purpose
Used to configure broadcast/multicast packet storm control. Shutdown mode is provided to
monitor the traffic rate in addition to the storm control drop mode. If traffic rate is too high, this
port will be shut down.
Syntax
config traffic control [<portlist> | all] {broadcast [enable| disable] | multicast [enable |
disable] | [dlf | unicast ] [enable | disable] | action [ drop | shutdown ] | threshold
<value 0-255000 > | countdown [<min 0> | <min 3-30> | disable] | time_interval <sec 5-
600>}
Description
The config traffic control command configures broadcast/multicast/DLF storm control.
Parameters
portlist
- Used to specify a range of ports to be configured.
broadcast
- Enable or disable broadcast storm control.
