Cisco Cisco 12000 Series 12-Port DS3 Line Card

The following sections provide procedures for configuring and troubleshooting the ATM line card.

To display current port configuration information, use the show running-config command. During 
power-on, the interface on a new ATM line card is shut down. To enable the interface, you must enter a 
no shutdown command in configuration mode. When the ATM line card is enabled (taken out of 
shutdown) with no additional configuration commands applied, the default interface configuration file 
parameters listed in 

 are used.

To enter a no shutdown command for the ATM line card interface or to change the configuration of the 
interface, you must enter configuration mode by using the configure privileged EXEC command.

After you verify that the new ATM line card is installed correctly, use the configure command to 
configure the new interface. Be prepared with the information that you will need, such as the interface 
IP address.

The following procedure is for creating a basic configuration—enabling an interface and specifying IP 
routing. You might also need to enter other configuration subcommands, depending on the requirements 
for your router configuration.

(For descriptions of configuration subcommands and the configuration options available, refer to the 
appropriate software publications in the 

Maximum transmission unit (mtu)

[no] mtu bytes

4470 bytes

Maximum numbers of virtual circuits

atm maxvc

2047

Loopback [no] loopback [diagnostic | line] no 

loopback

Internal clock

atm clock internal

line clock:
no atm clock internal

SONET framing

atm sonet stm-4 or 
atm sonet stm-1

SONET framing:
no atm sonet stm-4
no atm sonet stm-1