Allied Telesis AT-S63 - Manual (Page 144)

Chapter 7: Port Parameter Commands
144 Section I: Basic Operations
field does not apply to a fiber optic port. To adjust a port’s MDI/MDIX
setting, refer to “SET SWITCH PORT” on page 131.
ˆ Actual Speed/Duplex - Displays the current operating speed and
duplex mode of a port. This field displays no value (—) if the port does
not have a link to an end node or has been disabled.
ˆ Actual MDI Crossover- Displays the current operating MDI/MDIX
setting of a twisted pair port. This field displays no value (—) if the port
does not have a link to an end node or has been disabled. This field
does not apply to a fiber optic port.
ˆ Flow Control Status and Flow Control Threshold - Displays the status
of flow control on a port. Flow control applies to ports operating in full
duplex mode and is used by a port to stop an end node from sending
packets when its ingress buffer is full. The default setting is disabled.
The threshold marks the point at which flow control is activated. The
threshold is measured in cells of 128 bytes. The range is 1 to 7935
cells. The default value is 7935 cells.To set flow control, refer to
“DISABLE SWITCH PORT FLOW” on page 125, “ENABLE SWITCH
PORT FLOW” on page 128, or “SET SWITCH PORT” on page 131.
ˆ Backpressure Status and Backpressure Threshold - Displays the
status of backpressure on a port. Backpressure applies to ports
operating in half duplex mode. A port uses backpressure to stop an
end node from sending packets when its ingress buffer is full. The
default setting is disabled. The threshold marks the point at which
backpressure is activated. The threshold is measured in cells of 128
bytes. The range is 1 to 7935 cells. The default value is 7935 cells.To
set backpressure, refer to “SET SWITCH PORT” on page 131.
ˆ HOL Blocking Prevention Threshold - Displays the threshold at which
the switch signals a head of line blocking event. This event occurs
when switch ports are unable to forward packets to another switch port
because its egress queues are full. The switch responds to this event
by instructing the other switch ports to discard any packets in their
ingress queues that are destined for the oversubscribed port. The
threshold is measured in cells of 128 bytes. The range is 0 to 8191
cells. The default is 682.
ˆ Broadcast Ingress Filtering - Displays the status of ingress broadcast
filtering. If enabled, the port discards all ingress broadcast packets.
The default is disabled. To configure this parameter, refer to “SET
SWITCH PORT FILTERING” on page 135.
ˆ Broadcast Egress Filtering - Displays the status of egress broadcast
filtering. If enabled, the port discards all egress broadcast packets. The
default is disabled. To configure this parameter, refer to “SET SWITCH
PORT FILTERING” on page 135.
ˆ Unknown Multicast Ingress Filtering - Displays the status of unknown
ingress multicast filtering. If enabled, the port discards all unknown
ingress multicast packets. The default is disabled. To configure this
parameter, refer to “SET SWITCH PORT FILTERING” on page 135.