Assigning A Mac Address - Cisco 10000 Series Configuration Manual

Configuration Commands
The default configuration is auto-negotiation enabled.
Use the no form of the command to disable negotiation.
Note Both sides must be enabled for auto-negotiation, or the link does not come up.
In the following example, negotiation is disabled:
Router(config)# interface GigabitEthernet 1/0/0
Router(config-if)# no negotiation auto

Assigning a MAC Address

To assign a specific MAC address to a 1-Port Gigabit Ethernet Half-Height line card interface, use the
mac-address command:
mac-address address
[no] mac-address address
Where address assigns a user-defined MAC address to a Gigabit Ethernet interface. The MAC address
takes the form xxxx.xxxx.xxxx, where xxxx represents a 2-byte hexadecimal value.
Use the mac-address command to preserve a MAC address when you move a card to a new slot or
Tip
chassis. You may want to preserve the MAC address if you have an access list that refers to it. If you use
this command, you should change the address on the original slot so that you do not have two slots with
the same address.
Use no mac-address to restore the default MAC address.
Use the show interfaces GigabitEthernet slot/subslot/port command to see the MAC address.
In the following example, a new MAC address is assigned:
Router(config)# interface GigabitEthernet 1/0/0
router(config-if)# mac-address 6000.0001.0003
Setting and Changing Loopback Mode
To set the loopback mode on a 1-Port Gigabit Ethernet Half-Height line card interface, use the loopback
command in interface configuration mode.
loopback [internal | external]
[no] loopback [internal | external]
Where:
•
•
Use the no form of the command to stop the loopback.
For more information about this command, refer to the
Troubleshooting
Cisco 10000 Series Router Line Card Configuaration Guide
10-4
external runs a loopback that requires a loopback connector.
internal runs a loopback at the MAC controller.
Guide.
Chapter 10 1-Port Gigabit Ethernet Half-Height Line Card Configuration
Cisco 10000 Series Internet Router
OL-8834-04