Specifications

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Cisco 12000 Series Internet Router Configuration Guide for Cisco IOS Release 12.0S
Chapter 2 Basic Configuration of the Cisco 12000 Series Internet Router
Configuration Tasks
Configuring Line Card Interfaces
Because of the wide variety of line cards supported by the Cisco 12000 Series Internet Router, you
should refer to the configuration note that is available for each particular card for interface configuration
information. This section provides several examples to demonstrate how to configure line cards using
both the global configuration mode and the setup facility.
Configuring a POS Line Card
To configure a POS line card, perform the following procedure. The IP address and subnet mask are
examples only. You will need to obtain this information from your network administrator.
Additional configuration tasks can be performed for the line card in interface configuration mode. Refer
to the installation note provided with the line card for additional information.
Note By default, POS interfaces use the 32-bit cyclic redundancy check (CRC) and high-level data link control
(HDLC) as the encapsulation protocol.
The following commands are also useful for configuring POS interfaces:
The following sample excerpt from a setup command facility session for a 4-port OC-3c/STM-1c POS
line card shows settings for a typical configuration:
Configuring interface POS3/0:
Is this interface in use?: yes
Configure IP on this interface?: yes
Configure IP unnumbered on this interface?: no
IP address for this interface: 2.1.1.1
Number of bits in subnet field: 0
Class A network is 2.0.0.0, 0 subnet bits; mask is 255.0.0.0
Configure CLNS on this interface?: yes
If additional configuration is required, use the global configuration mode as described at the beginning
of this section.
Command Purpose
Step 1
Router(config)# interface pos 3/0
Enters interface configuration mode on the POS interface located
in slot 3 and port 0.
Step 2
Router(config-if)# ip address 2.1.1.1
255.0.0.0
Specifies the IP address and subnet mask for the interface.
Step 3
Router(config-if)# no shutdown
Changes the shutdown state to up and enables the interface. If you
configure an interface using the command line interface, you must
use this command to enable the interface. When you use the setup
command facility, this is performed automatically.
Command Purpose
Router(config-if)# pos scramble-atm
Enables SONET payload scrambling on a POS interface.
Router(config-if)# clock source internal
Controls which clock a POS interface will use to clock its transmitted
data.