9-9
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 9 Configuring Interfaces
Configuring Optional Interface Features
The ports on both ends of a link must have the same setting. The link will not come up if the ports at
each end of the link are set inconsistently (link negotiation enabled on one port and disabled on the other
port).
Table 9-1
shows the four possible link negotiation configurations and the resulting link status for each
configuration.
To configure link negotiation on a port, perform this task:
This example shows how to enable link negotiation on Gigabit Ethernet port 5/4:
Router(config)#
interface gigabitethernet 5/4
Router(config-if)#
no speed
nonegotiate
Displaying the Speed and Duplex Mode Configuration
To display the speed and duplex mode configuration for a port, perform this task:
This example shows how to display the speed and duplex mode of Fast Ethernet port 5/4:
Router#
show interfaces fastethernet 5/4
FastEthernet5/4 is up, line protocol is up
Hardware is Cat6K 100Mb Ethernet, address is 0050.f0ac.3058 (bia 0050.f0ac.3058)
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)
Full-duplex, 100Mb/s
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:33, output never, output hang never
Table 9-1
Link Negotiation Configuration and Possible Link Status
Link Negotiation State
Link Status
Local Port
Remote Port
Local Port
Remote Port
Off
Off
Up
Up
On On
Up Up
Off
On
Up
Down
On Off
Down
Up
Command
Purpose
Step 1
Router(config)#
interface gigabitethernet
slot/port
Selects the port to be configured.
Step 2
Router(config-if)#
speed
nonegotiate
Disables link negotiation.
Router(config-if)#
no speed
nonegotiate
Reverts to the default configuration (link negotiation
enabled).
Command
Purpose
Router#
show interfaces
type
1
slot/port
1.
type
=
ethernet
,
fastethernet
,
gigabitethernet
, or
tengigabitethernet
Displays the speed and duplex mode configuration.