17
the loop condition. For more information, see “Enabling single-port loopback detection on an Ethernet
interface.”
Multi-port loopback detection is implemented on the basis of single-port loopback detection
configurations on Ethernet interfaces. To implement multi-port loopback detection, you must enable single-
port loopback detection on one or multiple Ethernet interfaces on the switch.
To configure multi-port loopback detection:
To do… Use the command… Remarks
1. Enter system view
system-view —
2. Enable multi-port loopback
detection
loopback-detection multi-port-
mode enable
Required
Disabled by default
To enable multi-port loopback detection, you must configure the loopback-detection multi-port-mode
enable and loopback-detection enable commands in system view, and configure the loopback-detection
enable command in the view of the related interfaces.
The single-port loopback detection function is available when the switch is performing multi-port loopback
detection.
Setting the MDI mode of an Ethernet interface
Optical interfaces do not support the MDI mode setting.
Use both crossover and straight-through Ethernet cables to connect copper Ethernet interfaces. To
accommodate these two types of cables, a copper Ethernet interface can operate in one of the following
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 following MDI modes:
• 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.
To enable the interface to communicate with its peer, ensure that the local transmit pins are connected to
the remote receive pins. If the interface can detect the connection cable type, set the interface in auto
MDI mode. If not, set its MDI mode using the following guidelines:
• When a straight-through cable is used, set the interface to work in the MDI mode different than its
peer.
• When a crossover cable is used, set the interface to work in the same MDI mode as its peer, or set
either end to work in auto mode.
To set the MDI mode of an Ethernet interface:
To do… Use the command… Remarks
1. Enter system view
system-view —
To Next Page
Loading...
