speed (Management interface view)

Function

The speed command sets the rate of an electrical GE interface.

The undo speed command restores the default rate of an electrical GE interface.

Ethernet view: speed .

GigabitEthernet view: speed .

By default, an interface uses the auto-negotiation mode.

Format

speed { 10 | 100 | 1000 | auto }

undo speed

Parameters

Parameter	Description	Value
10	Indicates a rate of 10 Mbit/s.	-
100	Indicates a rate of 100 Mbit/s.	-
auto	Indicates the auto-negotiation mode. It is recommended that Ethernet interfaces work in auto-negotiation mode provided that the interfaces support this mode. Auto-negotiation is disabled only when two ends of a link work at mismatched rates or duplex modes. In this case, you need to manually set the interface rate and duplex mode.	-
1000	Indicates a rate of 1000 Mbit/s. 1000M Ethernet networks are developed based on the IEEE802.3 Ethernet standards. The transmission rate of a 1000M Ethernet is 1 Gbit/s, which is ten times the transmission rate of an FE. The standards are IEEE802.3z for optical fibers and copper cables and IEEE802.3ab for twisted pair cables.	-

Views

Management interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
device-mgr	write

Usage Guidelines

Usage Scenario

In auto-negotiation mode, the local device automatically adjusts the interface rate and duplex mode based on the interface rate and duplex mode of the peer so that both ends can work in the same duplex mode at a highest possible speed.

On a large-scale Ethernet network, manually setting the interface rate and duplex mode, verifying the configurations of devices, and checking statistics about Ethernet interfaces require a great deal of time and human input. Therefore, it is recommended that manually setting the interface rate and duplex mode be adopted only when auto-negotiation of an Ethernet link fails or a problem occurs with auto-negotiation. When there is an auto-negotiation problem, you are recommended to upgrade software or hardware of the device to support the auto-negotiation standard defined in IEEE802.3u/z.

If both ends support auto-negotiation, the duplex mode with a lower priority is adopted. Interconnected devices working in auto-negotiation mode is the prerequisite to the auto-negotiation mechanism. If one end works in auto-negotiation mode while the other end works in fixed mode, the auto-negotiation mechanism does not take effect.

Manually setting the interface rate and duplex mode usually complicates network planning and maintenance, and incorrect setting may affect even interrupt normal communication on the network. During network planning, if the rate of the interface on the peer end of an Ethernet link is known, you can run the speed command to set the rate for the local interface. However, once the rate of the peer interface changes, the rate of the local interface does not change, which will affect the communication quality.

Configuration Impact

Changing the rate or the duplex mode of an interface interrupts network communication for a short period.

Rates of the Ethernet interfaces at the two ends of a link must be the same. If one end works at 10 Mbit/s while the other end works at 100 Mbit/s, the link is Down.

Precautions

If the rate of an interface is changed, the new rate takes effect only after the interface restarts automatically.

For Ethernet electrical interfaces, the speed, duplex, and negotiation auto commands are associated with one another:

If a rate is specified using the speed command, the duplex mode is automatically changed to full.

Example

# Set the rate of GigabitEthernetGigabitEthernet0/0/0 to 100 Mbit/s.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernetGigabitEthernet0/0/0
[~HUAWEI-GigabitEthernetGigabitEthernet0/0/0] speed 100