Cisco DSL Router Configuration and Troubleshooting Guide - Step-by-Step Configuration of PPPoE with a Static IP Address

Introduction


Your Internet Service Provider (ISP) has assigned a static public IP address to your Cisco Digital Subscriber Line (DSL) Router.



Prerequisites

Requirements

There are no specific requirements for this document.



Components Used

This document is not restricted to specific software and hardware versions.



Conventions

Refer to Cisco Technical Tips Conventions for more information on document conventions.



Configuration Procedures

Important: Before you begin, close all programs on the PC that might be monitoring your COM port. Devices such as PDAs and digital cameras often place programs in the system tray that render your COM port unusable for the configuration of your Cisco DSL Router.



Connect the Cisco DSL Router and Your PC

A console connection is made with a rolled cable and connects the console port of the Cisco DSL Router to a COM port on a PC. The console cable that is included with the Cisco DSL Router is a flat light blue cable. For more information on the pinouts of a rolled cable, or the pinouts of an RJ-45 to DB9 converter, refer to Cabling Guide for Console and AUX Ports.



Connect the RJ-45 connector on one end of a Cisco console cable to the console port of the Cisco DSL Router.



Connect the RJ-45 connector at the other end of the console cable to an RJ-45 to DB9 converter.



Connect the DB9 connector to an open COM port on your PC.



Start and Set Up HyperTerminal

Complete these steps:



Start the HyperTerminal program on the PC.



Set up your HyperTerminal session.



Assign a name to your session and click OK.



In the Connect To window, click Cancel.



Choose File > Properties.



From the Properties window, go to the Connect Using list and select the COM port where you connect the DB9 end of the console cable.



From the Properties window click Configure and fill in these values:



Bits per second: 9600



Data bits: 8



Parity: None



Stop bits: 1



Flow Control: None



Click OK.



From the Call menu, click Disconnect.



From the Call menu, click Call.



Press Enter until you see a router prompt on your HyperTerminal window.



Clear Existing Configurations on the Cisco DSL Router

Complete these steps:



Type enable at the router prompt in order to enter privileged mode.



Router>enable

Router#



!--- The # symbol indicates that you are in privileged mode.



Clear existing configurations on the router.



Router#write erase

Reload the router so that it boots with a blank startup configuration.



Router#reload

System configuration has been modified. Save? [yes/no]:no

Proceed with reload? [confirm]yes



!--- The router reload can take a few minutes.



After the router has reloaded, enter enable mode again.



Router>enable

Router#Configure the Cisco DSL Router

Complete these steps:



Configure service timestamp to properly log and display debug output in the troubleshooting section.



Router#configure terminal

Router(config)#service timestamps debug datetime msec

Router(config)#service timestamps log datetime msec

Router(config)#end

Disable the logging console on your Cisco DSL Router in order to suppress console messages that might be triggered while you configure the router.



Router#configure terminal

Router(config)#no logging console

Router(config)#end

Configure ip routing, ip subnet-zero, and ip classless in order to provide flexibility in routing configuration options.



Router#configure terminal

Router(config)#ip routing

Router(config)#ip subnet-zero

Router(config)#ip classless

Router(config)#end

Configure the global Point-to-Point Protocol over Ethernet (PPPoE) parameters.



Router#configure terminal

Router(config)#vpdn enable

Router(config)#no vpdn logging

Router(config)#vpdn-group pppoe

Router(config-vpdn)#request-dialin

Router(config-vpdn-req-in)#protocol pppoe

Router(config-vpdn-req-in)#end

Configure an IP address and subnet mask on the Cisco DSL Router Ethernet interface.



For Network Address Translation (NAT): Optional) Enable NAT inside on the Ethernet interface.



Router#configure terminal

Router(config)#interface ethernet 0

Router(config-if)#ip tcp adjust-mss 1452



!--- If the ip tcp adjust-mss 1452 command is not supported, try

!--- ip adjust-mss 1452. If this command is not supported,

!--- upgrade to the latest Cisco DSL Router software or follow the

!--- procedure in Possible Required Configuration Steps on the PC.



Router(config-if)#ip address



!--- For NAT:



Router(config-if)#ip nat inside

Router(config-if)#no shut

Router(config-if)#end

Configure the ATM interface of your Cisco DSL Router with an ATM permanent virtual circuit (PVC), encapsulation type, and dialer pool.



Router#configure terminal

Router(config)#interface atm 0

Router(config-if)#pvc

Router(config-if-atm-vc)#pppoe-client dial-pool-number 1

Router(config-if-atm-vc)#no shut

Router(config-if-atm-vc)#end

Configure the Dialer interface of your Cisco DSL Router for PPPoE with a static IP address.



For NAT: (Optional) Enable NAT outside on the Dialer interface.



Router#configure terminal

Router(config)#interface dialer 1

Router(config-if)#mtu 1492

Router(config-if)#ip

Router(config-if)#no ip directed-broadcast



!--- For NAT:



Router(config-if)#ip nat outside

Router(config-if)#encapsulation ppp

Router(config-if)#dialer pool 1

Router(config-if)#ppp chap hostname

Router(config-if)#ppp chap password

Router(config-if)#ppp pap sent-username password

Router(config-if)#end

Configure a default route using Dialer1 as the outbound interface.



Router#configure terminal

Router(config)#ip route 0.0.0.0 0.0.0.0 dialer1

Router(config)#end

For NAT: Configure global NAT commands on the Cisco DSL Router to allow sharing of the dynamic public IP address of the Dialer interface.



Router#configure terminal

Router(config)#ip nat inside source list 1 interface Dialer1 overload

Router(config)#access-list 1 permit



Router(config)#end

Optional Configurations



NAT Pool, if additional IP addresses have been provided by your ISP.



Router(config)#ip nat inside source list 1 interface dialer1 overload

Router(config)#ip nat pool

netmask

Router(config)#end

Static NAT, if Internet users require access to internal servers.



Router(config)#ip nat inside source static tcp

{80 or 25} {80 or 25} extendable

Router(config)#end

For Dynamic Host Configuration Protocol (DHCP): (Optional) Configure the Cisco DSL Router as a DHCP server with a pool of IP addresses to assign to hosts connected to the Ethernet interface of the Cisco DSL Router. The DHCP server dynamically assigns an IP address, Domain Name Server (DNS), and the default gateway IP address to your hosts.



Router#configure terminal

Router(config)#ip dhcp excluded-address

Router(config)#ip dhcp pool

Router(dhcp-config)#network

Router(dhcp-config)#default-router

Router(dhcp-config)#dns-server



Router(dhcp-config)#end

Enable logging console on the Cisco DSL Router, and then write all the changes to memory.



Router#configure terminal

Router(config)#logging console

Router(config)#end

*Jan 1 00:00:00.100: %SYS-5-CONFIG_I: Configured from console by console

Router#write memory

Building configuration... [OK]

Router#Configuration

This is the configuration that is built after you have completed the procedures in the Configuration Procedures section of this document.



Cisco DSL Router with a Static IP Address





!--- Comments contain explanations and additional information.





service timestamps debug datetime msec

service timestamps log datetime msec

vpdn enable

no vpdn logging

vpdn-group pppoe

request-dialin

protocol pppoe

!

!

ip subnet-zero

!



!--- For DHCP:



ip dhcp excluded-address

ip dhcp pool

network

default-router

dns-server

!

interface Ethernet0

no shut

ip address

ip tcp adjust-mss 1452



!--- If the ip tcp adjust-mss 1452 command is not supported, try this

!--- configuration statement: ip adjust-mss 1452. If this command is not

!--- supported in your current Cisco DSL Router software release, upgrade to the

!--- latest Cisco DSL Router software or follow the procedure in

!--- Possible Required Configuration Steps on the PC.





!--- For NAT:



ip nat inside

no ip directed-broadcast

!

interface atm0

no ip address

bundle-enable

dsl operating-mode auto

!

interface atm0.1 point-to-point

no ip address

no ip directed-broadcast

no atm ilmi-keepalive

pvc

pppoe-client dial-pool-number 1



!--- Common PVC values supported by ISPs are 0/35 or 8/35.

!--- Confirm your PVC values with your ISP.



!

!

interface dialer1

ip address

mtu 1492



!--- For NAT:



ip nat outside

encapsulation ppp

dialer pool 1

ppp chap hostname

ppp chap password

ppp pap sent-username password

!



!--- For NAT:



ip nat inside source list 1 interface dialer1 overload



!--- If you have a pool (a range) of public IP addresses provided

!--- by your ISP, you can use a NAT Pool. Replace

!--- ip nat inside source list 1 interface dialer1 overload









!--- with these two configuration statements:

!--- ip nat inside source list 1 pool overload

!--- ip nat pool

!--- netmask









!--- If Internet users require access to an internal server, you can

!--- add this static NAT configuration statement:

!--- ip nat inside source static tcp {80 or 25}

!--- {80 or 25} extendable

!--- Note: TCP port 80 (HTTP/web) and TCP port 25 (SMTP/mail) are used

!--- for this example. You can open other TCP or UDP ports, if needed.



!

ip classless

ip route 0.0.0.0 0.0.0.0 interface dialer1



!--- For NAT:



access-list 1 permit



!--- In this configuration, access-list 1 defines a standard access list

!--- that permits the addresses that NAT translates. For example, if

!--- your private IP network is 10.10.10.0, configure

!--- access-list 1 permit 10.10.10.0 0.0.0.255 in order to allow NAT to translate

!--- packets with source addresses between 10.10.10.0 and 10.10.10.255.



!

end





Verify

Your Cisco DSL Router is now operational for Asymmetric Digital Subscriber Line (ADSL) service. You can issue a show run command in order to see the configuration.



Router#show run

Building configuration...The Output Interpreter Tool ( registered customers only) (OIT) supports certain show commands. Use the OIT to view an analysis of show command output.



Troubleshoot

Refer to Troubleshooting PPPoE if your ADSL service does not work properly.



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