negotiation auto

Function

The negotiation auto command configures an Ethernet interface to work in auto-negotiation mode.

The undo negotiation auto command configures an Ethernet interface to work in non-auto negotiation mode.

By default, an Ethernet interface works in auto-negotiation mode.

Format

negotiation auto

undo negotiation auto

Parameters

None

Views

Ethernet interface view, GE interface view, XGE interface view, MultiGE interface view, 25GE interface view, port group view, Meth interface view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

Earlier Ethernet worked in 10M half-duplex mode and required mechanisms such as Carrier Sense Multiple Access (CSMA)/Collision Detection (CD) to ensure system stability. As Ethernet technology develops, full-duplex Ethernet and 100 Mbit/s Ethernet emerge. This greatly improves Ethernet performance. Auto-negotiation technology allows new Ethernet to be compatible with earlier Ethernet. In auto-negotiation mode, interfaces on both ends of a link negotiate their operating parameters, including the duplex mode and rate. If the negotiation succeeds, the two interfaces work at the same operating parameters.

Precautions

For details about Ethernet interfaces supporting the auto-negotiation function, see Licensing Requirements and Limitations for Ethernet Interfaces.
By default, auto-negotiation is enabled on GE optical interfaces and rate auto-negotiation is disabled. You can run the speed auto-negotiation command to enable rate auto-negotiation.
After configuring the auto-negotiation function on an interface, if you remove and install a single optical fiber on the interface, the interface may be Up and the remote interface may be Down. You can run the shutdown and undo shutdown commands on the remote interface to make the remote interface go Up.

Example

# Configure GE0/0/1 to work in non-auto negotiation mode.

<HUAWEI> system-view
[HUAWEI] interface gigabitethernet 0/0/1
[HUAWEI-GigabitEthernet0/0/1] undo negotiation auto