Specifications

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Catalyst 2950 and Catalyst 2955 Switch Command Reference

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Chapter 2 Cisco IOS Commands

speed

Use the speed interface configuration command to specify the speed of a port. Use the no form of this

command to return the port to its default value.

speed {10 | 100 | 1000 | auto| nonegotiate}

no speed

Note You cannot configure speed or duplex mode on Gigabit Interface Converter (GBIC) ports, but for certain

types of GBICs, you can configure speed to not negotiate (nonegotiate) if they are connected to a device

that does not support autonegotiation.

Syntax Description

Defaults For Fast Ethernet and 10/100/1000 ports, the default is auto.

For 100BASE-FX ports, the default is 100 Mbps.

For Gigabit Interface Converter (GBIC)-module ports, the default is 1000 Mbps.

Command Modes Interface configuration

Command History

Usage Guidelines Fast Ethernet ports, except for 100BASE-FX ports, can be configured at 10 or 100 Mbps. The

10/100/1000 ports can be configured at 10, 100, or 1000 Mbps and operate only in the full-duplex mode.

You cannot configure the speed on GBIC interfaces, but you can configure the speed to not negotiate

(nonegotiate) for the 1000BASE-SX, -LX, or -ZX GBICs, if they are connected to devices that do not

support autonegotiation. GBIC-module ports support only 1000 Mbps. The speed values of 10 Mbps

and 100 Mbps are not supported.

10 Port runs at 10 Mbps.

100 Port runs at 100 Mbps.

1000 Port runs at 1000 Mbps (only valid for Gigabit Ethernet ports).

auto Port automatically detects whether it should run at 10 or 100 Mbps on

Fast Ethernet ports or at 10, 100, or 1000 Mbps on 10/100/1000 ports.

nonegotiate Autonegotiation is disabled and the port runs at 1000 Mbps. This option is

valid and visible only on 1000BASE-X, -LX, and -ZX GBIC ports.

Gigastack GBICs and 1000BASE-T GBICs do not suport disabling of

autonegotiation.

Release Modification

12.0(5.2)WC(1) This command was first introduced.

12.1(11)EA1 The nonegotiate keyword was added.