1.After the router has reloaded. enter enable mode again.
　　Router>enable
　　Router#
　　
　　2.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
　　
　　3.Disable logging console on your Cisco DSL Router to suppress console messages that may be triggered while you are configuring the router.
　　Router#configure terminal
　　Router(config)#no logging console
　　Router(config)#end
　　
　　4.Configure ip routing. ip subnet-zero. and ip classless 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
　　
　　5.Configure 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
　　
　　6.Configure an IP address and subnet mask on the Cisco DSL Router Ethernet interface.
　　(Optional) Enable NAT inside on the Ethernet interface.
　　Router#configure terminal
　　Router(config)#interface ethernet 0
　　Router(config-if)#ip tcp adjust-mss 1452/ip adjust-mss 1452
　　Router(config-if)#ip address 192.168.1.2 255.255.255.252
　　Router(config-if)#ip nat inside
　　Router(config-if)#no shut
　　Router(config-if)#end
　　
　　7.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 0/35 (Guizhou Province)
　　Router(config-if-atm-vc)#pppoe-client dial-pool-number 1
　　Router(config-if-atm-vc)#no shut
　　Router(config-if-atm-vc)#end
　　
　　8.Configure the Dialer interface of your Cisco DSL Router for Point-to-Point Protocol over ATM (PPPoA) to enable a dynamic IP address to be assigned.
　　(Optional) Enable NAT outside on the Dialer interface.
　　Router#configure terminal
　　Router(config)#interface dialer 1
　　Router(config-if)#ip address negotiated
　　Router(config-if)#mtu 1492
　　Router(config-if)#no ip directed-broadcast
　　Router(config-if)#ip nat outside
　　Router(config-if)#encapsulation ppp
　　Router(config-if)#dialer pool 1
　　Router(config-if)#ppp auth chap hostname heiye
　　Router(config-if)#ppp auth chap password heiye
　　Router(config-if)#ppp auth pap sent-username heiye password heiye
　　Router(config-if)#end
　　
　　9.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
　　
　　10.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 192.168.1.3 0.0.0.255
　　Router(config)#end
　　
　　11.Optional Configurations
　　NAT Pool. if additional IP addresses have been provided by your ISP.
　　Router(config)#ip nat inside source list 1 pool ciscooverload
　　Router(config)#ip nat pool cisco 200.1.1. 200.1.1.254 netmask 255.255.255. 0
　　Router(config)#end
　　
　　12.
　　Static NAT. if Internet users require access to internal servers.
　　Router(config)#ip nat inside source static tcp 192.168.1.5 80 200.1.1.5 80 extendable
　　Router(config)#end
　　
　　13.(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 192.168.21.2(E0 ip address)
　　Router(config)#ip dhcp pool wang
　　Router(dhcp-config)#network 192.168.1.2 255.255.255.0
　　Router(dhcp-config)#default-router 192.168.1.2
　　Router(dhcp-config)#dns-server 202.98.198.168 202.98.192.68
　　Router(dhcp-config)#end
　　
　　14.Enable the logging console on the Cisco DSL Router, and 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/copy run start
　　Building configuration... [OK]
　　Router#show run
　　Router#show ip int brief
　　to view the IP interface status.
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