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Catalyst 3560 Switch Command Reference
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Chapter 2 Catalyst 3560 Switch Cisco IOS Commands
speed
speed
Use the speed interface configuration command to specify the speed of a 10/100 Mbps or
10/100/1000 Mbps port. Use the no or default form of this command to return the port to its default
value.
speed {10 | 100 | 1000 | auto [10 | 100 | 1000] | nonegotiate}
no speed
Syntax Description
Defaults The default is auto.
Command Modes Interface configuration
Command History
Usage Guidelines Except for the 1000BASE-T SFP modules, if an SFP module port is connected to a device that does not
support autonegotiation, you can configure the speed to not negotiate (nonegotiate).
If the speed is set to auto, the switch negotiates with the device at the other end of the link for the speed
setting and then forces the speed setting to the negotiated value. The duplex setting remains as
configured on each end of the link, which could result in a duplex setting mismatch.
If both ends of the line support autonegotiation, we highly recommend the default autonegotiation
settings. If one interface supports autonegotiation and the other end does not, do use the auto setting on
the supported side, but set the duplex and speed on the other side.
Caution Changing the interface speed and duplex mode configuration might shut down and re-enable the
interface during the reconfiguration.
For guidelines on setting the switch speed and duplex parameters, see the “Configuring Interface
Characteristics” chapter in the software configuration guide for this release.
10 Port runs at 10 Mbps.
100 Port runs at 100 Mbps.
1000 Port runs at 1000 Mbps. This option is valid and visible only on 10/100/1000
Mbps-ports.
auto Port automatically detects the speed it should run at based on the port at the other
end of the link. If you use the 10, 100, or 1000 keywords with the auto keyword, the
port only autonegotiates at the specified speeds.
nonegotiate Autonegotiation is disabled, and the port runs at 1000 Mbps. (
Release Modification
12.1(19)EA1 This command was introduced.
12.2(20)SE1 Support for the 10, 100, and 1000 keywords with the auto keyword was added.