Allied Telesis AT-S97 User Manual
Page 84
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Chapter 5: Port and Module Commands
84
For example, if the network device connected to the twisted pair port of a
media converter channel is only capable of half-duplex mode, than both
ports of the channel and the network device connected to the fiber optic
port in the channel should be configured to operate in half-duplex mode,
too.
Also featured on the twisted pair ports of a media converter module is
auto-MDI/MDI-X, which automatically adjusts the wiring configuration of a
twisted pair port to either MDI or MDI-X, depending on the wiring
configuration of the end node. This feature allows the use of a straight-
through twisted pair cable regardless of the wiring configuration of the port
on the network device.
The auto-MDI/MDI-X feature is only available when a twisted pair port is
using Auto-Negotiation, the default setting. Disabling Auto-Negotiation
and manually configuring a port’s speed and duplex mode also disables
this feature. The wiring configuration of a port defaults to the MDI-X
setting. Disabling Auto-Negotiation may require the manual configuration
of the MDI/MDI-X setting on a port or the use a crossover cable,
depending on the wiring configuration of the network device connected to
the port on the module.
The INGRESS-RATE-LIMIT and EGRESS-RATE-LIMIT parameters
control the flow of network traffic to and from a port in a channel to its
network device. The rate limits, which are in kilobits and megabits per
second, can be applied separately to the two ports of a channel. The rate
limits can be used for storm prevention and to protect against the
formation of bottlenecks in a network topology,
The INGRESS-RATE-LIMIT feature controls the number of bits per
second a port accepts from the device connected to it. The port discards
frames after the limit is exceeded. For example, an ingress rate limit of
128k limits a port to no more than 128 kilobits per second in traffic flow
from its network device.
The EGRESS-RATE-LIMIT controls the number of bits per second a port
transmits to the network device connected to it.
The INGRESS-RATE-LIMIT and EGRESS-RATE-LIMIT parameters are
not supported on the 10/100/100Base-T Management port on the
management module.
Examples
This command disables Auto-Negotiation of the twisted pair port in
channel 5 of a media converter module and sets the port’s speed and
duplex mode to 100 Mbps, half-duplex. The module is in slot 2 of a chassis
with the ID number 0. Call-outs in the example identify the parts of the ID
number: