negotiation auto

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

Only MEth, GE, 10GE, and WAN interfaces support this command. A 10GE interface supports this command only when it has a GE optical module installed.

When a GE optical module is installed on a 10GE interface, the interface automatically switches to auto-negotiation mode and supports this command. When a GE optical module is removed from a 10GE interface, the interface automatically switches to non-auto-negotiation mode and does not support this command. If a GE optical module is removed from and then installed again on an interface, the interface retains the original configuration. When the non-auto-negotiation mode is configured for a 10GE interface that has a GE optical module installed, if the GE optical module is removed during the device restart after the configuration is saved, the interface still works in non-auto-negotiation mode.

When a GE copper module is installed on a 10GE interface, the interface automatically switches to auto-negotiation mode but does not support this command. When a GE copper module is removed from a 10GE interface, the interface automatically switches to non-auto-negotiation mode and does not support this command.

When a GE optical interface has a copper module installed, the interface automatically switches to the auto-negotiation mode, but this command cannot be configured. If the undo negotiation auto command has been run on the interface before a copper module is installed, the undo negotiation auto command is cleared after the copper module is installed, and the interface still works in auto-negotiation mode after the copper module is removed.

Before configuring the rate of the interface, you need to delete the auto-negotiation mode of the interface.

If the auto-negotiation mode is enabled on the GE optical interface, the two connected ends must enable the auto-negotiation mode.

If a GE electrical interface works at 1000 Mbit/s, it can work only in auto-negotiation but not forcible mode.

When the undo negotiation auto command is run on a combo interface serving as an electrical or optical interface, different Buildrun information is generated.

• Electrical interface:

  port-media-type copper
    undo negotiation auto

• Optical interface:

  port-media-type fiber
    undo negotiation auto