The speed command sets the rate of an electrical GE interface.
The undo speed command restores the default rate of an electrical GE interface.
By default, an interface uses the auto-negotiation mode.
This command is supported only on the NetEngine 8000 F1A.
Parameter | Description | Value |
---|---|---|
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. |
- |
10 |
Indicates a rate of 10 Mbit/s. |
- |
1000 |
Indicates a rate of 1000 Mbit/s, which is provided only by interfaces on a master control board. 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. |
- |
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.Prerequisites
The interface where the speed command is to be run is an electrical interface.
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
The GE mode of the subcard uses electrical modules and does not support the speed 10 configuration.
The rate of the GE optical interface is fixed at 1000 Mbit/s, which cannot be changed by using this command. If the rate of an interface is changed, the new rate takes effect only after the interface restarts automatically. When a GE/FE optical interface does not have any module inserted, the speed { 10 | 100 | 1000 | auto } command can be run, but the command configuration will be deleted if an optical or electrical module inserted into the interface does not support this command. For example, if an optical module that does not support the speed 10 command is inserted into an optical interface that has the speed 10 command configuration, the speed 10 command configuration will be deleted. If an optical or electrical module inserted into the interface supports this command, the command configuration will be retained. GE/FE optical interfaces with FE optical modules do not support the speed command. For Ethernet electrical interfaces, the speed, duplex, and negotiation auto commands are associated with one another: