Cisco Catalyst 3550 Command Reference Manual page 110

duplex
Changing the interface speed and duplex mode configuration might shut down and reenable the interface
Caution
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 configure an interface for full duplex operation:
Switch(config)# interface gigabitethernet0/1
Switch(config-if)# duplex full
You can verify your setting by entering the show interfaces privileged EXEC command.
Related Commands Command
show interfaces
speed
Catalyst 3550 Multilayer Switch Command Reference
2-84
Description
Displays the interface settings on the switch.
Sets the speed on a 10/100/1000 Mbps interface.
Chapter 2 Cisco IOS Commands
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