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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter8 Configuring Interface Cha rac teristics Configuring Layer 2 Interfaces
Beginning in pri v i le ged EXEC mode, f o l l o w t hese steps to set the speed and duplex mode for a physical
interface:
Use the no speed and no duplex interface configuration commands to return the interface to the default
speed and duplex settings (autonegotiate). To return all interface settings t o the def aults, use the default
interface interface-id interface configuration command.
This example shows how to set the interface speed to 10 Mbps and the duplex mode to half on
FastEthernet interface0/3 and to verify the configuration:
Switch# configure terminal
Switch(config)# interface fastethernet0/3
Switch(config-if)# speed 10
Switch(config-if)# duplex half
Switch(config-if)# end
Switch# show interfaces fastethernet0/3
FastEthernet0/3 is up, line protocol is down
Hardware is Fast Ethernet, address is 0000.0000.0003 (bia 0000.0000.0003)
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Half-duplex, 10Mb/s
input flow-control is off, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Enter interface configuration mode and the physical interface
identification.
Step3 speed {10 | 100 | 1000 | auto | nonegotiate} Enter the appropriate speed parameter for the interface, or enter
auto or nonegotiate.
Note The 1000 keyword is available only for 10/100/1000 Mbps
ports. The nonegotiate keyword is available only for
1000BASE-SX, -LX, and -ZX GBIC ports.
Step4 duplex {auto | full | half} Enter the duplex parameter for the interface.
Step5 end Return to privileged EXEC mode.
Step6 show interfaces interface-id Display the interface speed and duplex mode configuration.
Step7 copy running-config startup-config (Optional) Save your entries in the configuration file.