Setting The Mdi Mode Of An Ethernet Interface - HP 3100 Series Configuration Manual

Step
Enter Ethernet
5.
interface view or port
group view.
Enable loopback
6.
detection on the
interface.
Enable loopback
7.
detection control on
a trunk port or a
hybrid port.
Enable loopback
8.
detection in all the
VLANs on the trunk
or hybrid port.
Set the protective
9.
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 playing 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.
•
In auto mode, the interface negotiates pin roles with its peer.
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 | shutdown }
11
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 does not
receive or send 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.