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Cisco1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-02
Chapter1 Basic Router Configuration
Configuring Basic Parameters
Configure the Wireless Interface
The wireless interface enables connection to the router through a wireless LAN connection. For more
information about configuring a wireless connection, see Chapter9, “Configuring a Wireless LAN
Connection” and the Cisco Access Router Wireless Configuration Guide.
Configuring a Loopback Interface
The loopback interface acts as a placeholder for the static IP address and provides default routing
information.
For complete information on the loopback commands, see the CiscoIOS Release 12.3
documentationset.
Perform these steps to configure a loopback interface:
Configuration Example
The loopback interface in this sample configuration is used to support Network Address Translation
(NAT) on the virtual-template interface. This configuration example shows the loopback interface
configured on the Fast Ethernet interface with an IP address of 200.200.100.1/24, which acts as a static
IP address. The loopback interface points back to virtual-template1, which has a negotiated IP address.
!
interface loopback 0
ip address 200.200.100.1 255.255.255.0 (static IP address)
ip nat outside
!
interface Virtual-Template1
ip unnumbered loopback0
no ip directed-broadcast
ip nat outside
Command Purpose
Step1 interface type number
Example:
Router(config)# interface Loopback 0
Router(config-int)#
Enters interface configuration mode.
Step2 ip address ip-address mask
Example:
Router(config-int)# ip address 10.108.1.1
255.255.255.0
Router(config-int)#
Sets the IP address and subnet mask for the
loopback interface.
Step3 exit
Example:
Router(config-int)# exit
Router(config)#
Exits configuration mode for the loopback
interface and returns to global configuration
mode.