Allied Telesis AT-8100 Series - Manual (Page 206)

Chapter 10: Port Parameter Commands
206
BACKPRESSURE
Syntax
backpressure on|off
Parameters
on
Activates backpressure on the ports.
off
Deactivates backpressure on the ports.
Mode
Port Interface mode
Description
Use this command to enable or disable backpressure on ports that are
operating at 10 or 100 Mbps in half-duplex mode. Backpressure is used by
ports during periods of packet congestion to temporarily stop their network
counterparts from transmitting more packets. This prevents a buffer
overrun and the subsequent loss and retransmission of network packets.
A port initiates backpressure by transmitting on the shared link to cause a
data collision, which causes its link partner to cease transmission.
To set backpressure on a port, you must configure the speed and duplex
mode manually. You cannot set backpressure on a port that is using Auto-
Negotiation.
Confirmation Command
“SHOW RUNNING-CONFIG” on page 170
Examples
This example configures port 15 to 10 Mbps, half-duplex mode, and
activates backpressure:
awplus> enable
awplus# configure terminal
awplus(config)# interface port1.0.15
awplus(config-if)# speed 10
awplus(config-if)# duplex half
awplus(config-if)# backpressure on