Configure The Loopback Interface; Configure The Lan Interface; Create The Group Asynchronous Interface - Cisco 2611XM Software Configuration Manual

Chapter 3 Configuring with the Command-Line Interface
For more information about configuring T1 ISDN D-channel serial interfaces, refer to the "Configure
ISDN PRI" section in the Cisco IOS Release 11.3 Dial Solutions Configuration Guide.

Configure the Loopback Interface

The loopback 0 interface is the interface dial-in users access when dialing in to the network. Usually, all
dial-in users are assigned to a single IP subnet. This subnet can be identified with the loopback 0
interface, a logical interface whose network number can be borrowed by each asynchronous dial-in
interface.
To configure the loopback 0 interface, perform the following tasks, beginning in global configuration
mode:
Step 1
Step 2

Configure the LAN Interface

The next task you need to perform is to configure the LAN interfaces on your Cisco 3600 series router.
For the purpose of this procedure, we are showing how to configure an Ethernet interface. If the interface
you are configuring is different, refer to the "Configuring LAN Interfaces" chapter in the Cisco IOS
Release 11.3 Configuration Fundamentals Configuration Guide or to the configuration notes that
shippedwith your module.
To configure an Ethernet interface, perform the following tasks, beginning in global configuration mode:
Step 1
Step 2
Step 3
The Ethernet and loopback interfaces should be on different subnets.
Note

Create the Group Asynchronous Interface

A group asynchronous interface is a parent interface that applies protocol characteristics to specified,
associated asynchronous interfaces. After you create a group asynchronous interface, all associated
asynchronous interfaces (called members) can be configured through it. Group asynchronous interfaces
can speed configuration time and help you maintain interface configuration consistency.
OL-1957-03
Command
interface Loopback number
ip address ip-address ip-address
mask
Command
interface ethernet slot/port
ip address ip-address ip-address
mask
no shutdown
Software Configuration Guide for Cisco 2600 Series, Cisco 3600 Series, and Cisco 3700 Series Routers
Configuring the Digital Modem Network Module for the Cisco 3640 Router
Description
Select the loopback 0 interface.
Assign an IP address and subnet mask to
the loopback 0 interface.
Description
Select the Ethernet interface.
Assign an IP address and subnet mask to
the Ethernet interface.
Enable this interface
3-55