Setting The Mdi Mode Of An Ethernet Interface - H3C S3600V2 SERIES Layer 2-Lan Switching Configuration Manual

Step
5. Enter Ethernet
interface view or port
group view.
6. Enable loopback
detection on the
interface.
7. Enable loopback
detection control on a
trunk port or a hybrid
port.
8. Enable loopback
detection in all the
VLANs on the trunk or
hybrid port.
9. Set the protective
action to take on the
interface when a loop
is detected.

Setting the MDI mode of an Ethernet interface

IMPORTANT:
Fiber ports do not support the MDI mode setting.
You can use both crossover and straight-through Ethernet cables to connect copper Ethernet interfaces.
To accommodate these types of cables, a copper Ethernet interface can operate in one of the following
Medium Dependent Interface (MDI) modes:
Across mode
•
Normal mode
•
Auto mode
•
A copper Ethernet interface uses an RJ-45 connector, which comprises eight pins, each of which plays a
dedicated role. For example, pins 1 and 2 transmit signals, and pins 3 and 6 receive signals. The pin
role varies by the MDI modes as follows:
In normal mode, pins 1 and 2 are transmit pins, and pins 3 and 6 are receive pins.
•
• In across mode, pins 1 and 2 are receive pins, and pins 3 and 6 are transmit pins.
Command
•
Enter Ethernet interface view:
interface interface-type
interface-number
•
Enter port group view:
port-group manual
port-group-name
loopback-detection enable
loopback-detection control
enable
loopback-detection per-vlan
enable
loopback-detection action
{ no-learning | semi-block |
shutdown }
13
Remarks
Use either command.
To configure loopback detection on one
interface, enter Ethernet interface view.
To configure loopback detection on a group
of Ethernet interfaces, enter port group view.
Disabled by default.
Optional.
Disabled by default.
Optional.
By default, a trunk or hybrid port performs
loopback detection only in its port VLAN ID
(PVID).
Optional.
By default, a looped interface drops the
incoming packets and correctly sends
packets the system generates traps and log
messages, and deletes all MAC address
entries of the looped interface.
With the shutdown keyword specified, the
switch shuts down the looped ports and set
their physical state to Loop down. When a
looped port recovers, you must use the undo
shutdown command to restore its forwarding
capability.