Specifications
Table Of Contents
- Contents
- Preface
- Getting Started
- Basic Router Configuration
- Interface Port Labels
- Viewing the Default Configuration
- Information Needed for Configuration
- Configuring Basic Parameters
- Configuring Static Routes
- Configuring Dynamic Routes
- Configuring Enhanced IGRP
- Basic Router Configuration
- Configuring Your Router for Ethernet and DSL Access
- Sample Network Deployments
- Configuring PPP over Ethernet with NAT
- Configuring PPP over ATM with NAT
- Configuring a LAN with DHCP and VLANs
- Configuring a VPN Using Easy VPN and an IPSec Tunnel
- Configure the IKE Policy
- Configure Group Policy Information
- Apply Mode Configuration to the Crypto Map
- Enable Policy Lookup
- Configure IPSec Transforms and Protocols
- Configure the IPSec Crypto Method and Parameters
- Apply the Crypto Map to the Physical Interface
- Create an Easy VPN Remote Configuration
- Verifying Your Easy VPN Configuration
- Configuration Example
- Configuring VPNs Using an IPSec Tunnel and Generic Routing Encapsulation
- Configuring a Simple Firewall
- Configuring a Wireless LAN Connection
- Sample Configuration
- Configuring Additional Features and Troubleshooting
- Additional Configuration Options
- Configuring Security Features
- Configuring Dial Backup and Remote Management
- Troubleshooting
- Reference Information
- Cisco IOS Software Basic Skills
- Concepts
- ROM Monitor
- Common Port Assignments

5-2
Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-03
Chapter 5 Configuring a LAN with DHCP and VLANs
Configure DHCP
• Configure VLANs
Note The procedures in this chapter assume you have already configured basic router features as well as
PPPoE or PPPoA with NAT. If you have not performed these configurations tasks, see
Chapter 1, “Basic
Router Configuration,” Chapter 3, “Configuring PPP over Ethernet with NAT,” and Chapter 4,
“Configuring PPP over ATM with NAT” as appropriate for your router. See the Cisco IOS IP
Configuration Guide to assign an IP address to the ports.
Configure DHCP
Perform these steps to configure your router for DHCP operation, beginning in global configuration
mode:
Command Purpose
Step 1
ip domain name name
Example:
Router(config)# ip domain name smallbiz.com
Router(config)#
Identifies the default domain that the router uses to
complete unqualified hostnames (names without a
dotted-decimal domain name).
Step 2
ip name-server server-address1
[server-address2...server-address6]
Example:
Router(config)# ip name-server 192.168.11.12
Router(config)#
Specifies the address of one or more Domain
Name System (DNS) servers to use for name and
address resolution.
Step 3
ip dhcp excluded-address low-address
[high-address]
Example:
Router(config)# ip dhcp excluded-address
192.168.9.0
Specifies IP addresses that the DHCP server
should not assign to DHCP clients. In this
example, we are excluding the router address.
Step 4
ip dhcp pool name
Example:
Router(config)# ip dhcp pool dpool1
Router(config-dhcp)#
Creates a DHCP address pool on the router and
enters DHCP pool configuration mode. The name
argument can be a string or an integer.
Step 5
network network-number [mask | prefix-length]
Example:
Router(config-dhcp)# network 10.10.0.0
255.255.255.0
Router(config-dhcp)#
Defines subnet number (IP) address for the DHCP
address pool, optionally including the mask.