9-8
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 9 Configuring Interfaces
Configuring Optional Interface Features
To configure the port speed for a 10/100 or a 10/100/1000-Mbps Ethernet port, perform this task:
Release 12.2(17a)SX and later releases support the
10 100 1000
keywords after the
auto
keyword. When
configuring the port speed for a 10/100/1000-Mbps Ethernet port with Release 12.2(17a)SX and later
releases, note the following:
•
Enter the
auto 10 100
keywords to restrict the negotiated speed to 10-Mbps or 100-Mbps.
•
The
auto 10 100 1000
keywords have the same effect as the
auto
keyword by itself.
This example shows how to configure the speed to 100 Mbps on the Fast Ethernet port 5/4:
Router(config)#
interface fastethernet 5/4
Router(config-if)#
speed 100
Setting the Interface Duplex Mode
Note
•
10-Gigabit Ethernet and Gigabit Ethernet are full duplex only. You cannot change the duplex mode
on 10-Gigabit Ethernet or Gigabit Ethernet ports or on a 10/100/1000-Mps port configured for
Gigabit Ethernet.
•
If you set the port speed to auto on a 10/100-Mbps or a 10/100/1000-Mbps Ethernet port, both speed
and duplex are autonegotiated. You cannot change the duplex mode of autonegotiation ports.
To set the duplex mode of an Ethernet or Fast Ethernet port, perform this task:
This example shows how to set the duplex mode to full on Fast Ethernet port 5/4:
Router(config)#
interface fastethernet 5/4
Router(config-if)#
duplex full
Configuring Link Negotiation on Gigabit Ethernet Ports
Note
Link negotiation does not negotiate port speed.
On Gigabit Ethernet ports, link negotiation exchanges flow-control parameters, remote fault
information, and duplex information. Link negotiation is enabled by default.
Command
Purpose
Step 1
Router(config)#
interface fastethernet
slot/port
Selects the Ethernet port to be configured.
Step 2
Router(config-if)#
speed
{
10
|
100
|
1000
|
{
auto
[
10
100
[
1000
]]}}
Configures the speed of the Ethernet interface.
Router(config-if)#
no speed
Reverts to the default configuration (speed auto).
Command
Purpose
Step 1
Router(config)#
interface fastethernet
slot/port
Selects the Ethernet port to be configured.
Step 2
Router(config-if)#
duplex
[
auto
|
full
|
half
]
Sets the duplex mode of the Ethernet port.
Router(config-if)#
no duplex
Reverts to the default configuration (duplex auto).
