Cisco Catalyst 3750 Command Reference Manual page 488

speed
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 both interfaces.
Changing the interface speed and duplex mode configuration might shut down and re-enable the
Caution
interface during the reconfiguration.
For guidelines on setting the switch speed and duplex parameters, refer to the software configuration
Note
guide for this release.
Examples This example shows how to set speed on a port to 100 Mbps:
Switch(config)# interface gigabitethernet1/0/1
Switch(config-if)# speed 100
You can verify your settings by entering the show interfaces privileged EXEC command.
Related Commands Command
duplex
show interfaces
Catalyst 3750 Switch Command Reference
2-462
Description
Specifies the duplex mode of operation for Fast Ethernet and Gigabit
Ethernet ports.
Displays the statistical information specific to all interfaces or to a specific
interface.
Chapter 2 Catalyst 3750 Switch Cisco IOS Commands
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