Cisco IOS version 15 : PPPoE setting ( source NAT )

Here's an explanation of setting up PPPoE on Cisco IOS ver 15.

[ Network Topology ]


[ configuration ]

R1 ( PPPoE Client Router )

PPPoE-Client#sh ver Cisco IOS Software, 7200 Software (C7200-ADVENTERPRISEK9-M), Version 15.0(1)M4, RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2010 by Cisco Systems, Inc. Compiled Thu 28-Oct-10 22:27 by prod_rel_team ROM: ROMMON Emulation Microcode BOOTLDR: 7200 Software (C7200-ADVENTERPRISEK9-M), Version 15.0(1)M4, RELEASE SOFTWARE (fc1) PPPoE-Client#show running-config Building configuration... Current configuration : 1859 bytes ! ! Last configuration change at 01:06:59 UTC Fri Apr 15 2011 ! upgrade fpd auto version 15.0 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname PPPoE-Client ! boot-start-marker boot-end-marker ! enable password hello ! no aaa new-model ! ! ! ip source-route ip cef ! ! ! ! no ip domain lookup no ipv6 cef ! multilink bundle-name authenticated ! ! ! ! ! ! ! ! ! redundancy ! ! ! ! ! ! ! ! ! ! interface FastEthernet0/0 no ip address shutdown duplex half ! ! interface Ethernet1/0 description WAN no ip address duplex half pppoe enable group global pppoe-client dial-pool-number 1 ! ! interface Ethernet1/1 description LAN ip address 10.0.0.254 255.255.255.0 ip nat inside ip virtual-reassembly ip tcp adjust-mss 1414 duplex half ! ! interface Ethernet1/2 no ip address shutdown duplex half ! ! interface Ethernet1/3 no ip address shutdown duplex half ! ! interface Ethernet1/4 no ip address shutdown duplex half ! ! interface Ethernet1/5 no ip address shutdown duplex half ! ! interface Ethernet1/6 no ip address shutdown duplex half ! ! interface Ethernet1/7 no ip address shutdown duplex half ! ! interface Dialer1 ip address negotiated ip mtu 1454 ip nat outside ip virtual-reassembly encapsulation ppp dialer pool 1 dialer-group 1 ppp authentication chap callin ppp chap hostname cisco ppp chap password 0 cisco ! ! ip forward-protocol nd no ip http server no ip http secure-server ! ! ip nat inside source list 101 interface Dialer1 overload ip route 0.0.0.0 0.0.0.0 Dialer1 ! access-list 101 permit ip 10.0.0.0 0.255.255.255 any dialer-list 1 protocol ip permit ! ! ! ! ! ! control-plane ! ! ! ! ! ! gatekeeper shutdown ! ! line con 0 stopbits 1 line aux 0 stopbits 1 line vty 0 password hello login line vty 1 4 login ! end PPPoE-Client#

R3 ( PPPoE Server Router )

PPPoE-Server#sh ver Cisco IOS Software, 3600 Software (C3640-JK9S-M), Version 12.4(13a), RELEASE SOFTWARE (fc1) Technical Support: http://www.cisco.com/techsupport Copyright (c) 1986-2007 by Cisco Systems, Inc. Compiled Tue 06-Mar-07 20:25 by prod_rel_team ROM: ROMMON Emulation Microcode ROM: 3600 Software (C3640-JK9S-M), Version 12.4(13a), RELEASE SOFTWARE (fc1) PPPoE-Server#sh running-config Building configuration... Current configuration : 1124 bytes ! version 12.4 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption ! hostname PPPoE-Server ! boot-start-marker boot-end-marker ! enable password hello ! no aaa new-model memory-size iomem 5 ! ! ip cef no ip domain lookup ip domain name domain ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! username cisco password 0 cisco ! ! ! ! ! ! bba-group pppoe global virtual-template 1 ! bba-group pppoe test virtual-template 1 ! ! interface Ethernet0/0 description WAN no ip address half-duplex pppoe enable group test ! interface Ethernet0/1 description LAN ip address 20.0.0.254 255.255.255.0 half-duplex ! interface Ethernet0/2 no ip address shutdown half-duplex ! interface Ethernet0/3 no ip address shutdown half-duplex ! interface Virtual-Template1 mtu 1454 ip address 10.0.0.1 255.255.255.0 peer default ip address pool test1 ppp authentication chap ! ip local pool test1 10.0.0.200 10.0.0.254 ip http server no ip http secure-server ! ! ! ! ! ! control-plane ! ! ! ! ! ! ! ! ! ! line con 0 line aux 0 line vty 0 password hello login line vty 1 4 login ! ! end PPPoE-Server#

[ R1 n’ R3 logs ]

R1 ( PPPoE Client )

PPPoE-Client#sh pppoe session     1 client session Uniq ID  PPPoE  RemMAC          Port                    VT  VA         State           SID  LocMAC                                      VA-st      Type    N/A     39  cc02.124b.0000  Et1/0                  Di1  Vi2        UP                      ca00.124b.001c                              UP               PPPoE-Client#

PPPoE-Client#sh logging *Apr 15 01:38:51.527: %DIALER-6-BIND: Interface Vi2 bound to profile Di1 *Apr 15 01:38:51.531: %LINK-3-UPDOWN: Interface Virtual-Access2, changed state to up *Apr 15 01:38:53.647: %LINEPROTO-5-UPDOWN: Line protocol on Interface Virtual-Access2, changed state to up

R3 ( PPPoE Server )

PPPoE-Server#sh pppoe session     1 session  in LOCALLY_TERMINATED (PTA) State     1 session  total Uniq ID  PPPoE  RemMAC          Port                    VT  VA         State           SID  LocMAC                                      VA-st     41     40  ca00.124b.001c  Et0/0                    1  Vi1.1      PTA                  cc02.124b.0000                              UP

[ confirm source IP of ubuntu-1 is NATed from 10.0.0.100 to 10.0.0.254 when accessing to ubuntu-2 ]

ubuntu-1 : 10.0.0.100
R1 :10.0.0.254
ubuntu-2 : 20.0.0.100

root@ubuntu-1:~# ifconfig eth0 | egrep "inet addr"          inet addr:10.0.0.100  Bcast:10.0.0.255  Mask:255.255.255.0 root@ubuntu-2:~# ifconfig eth0 | egrep -i "inet addr"          inet addr:20.0.0.100  Bcast:20.0.0.255  Mask:255.255.255.0

ping to ubuntu-2 on ubuntu-1 n’ capture ping traffics on ubuntu-2

ping succeed n’ source IP of ubuntu-1 is NATed

root@ubuntu-1:~# ping 20.0.0.100 -c 1 PING 20.0.0.100 (20.0.0.100) 56(84) bytes of data. 64 bytes from 20.0.0.100: icmp_seq=1 ttl=62 time=16.4 ms --- 20.0.0.100 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 16.445/16.445/16.445/0.000 ms

root@ubuntu-2:~# tshark -i eth0 icmp Running as user "root" and group "root". This could be dangerous. Capturing on eth0  0.000000   10.0.0.254 -> 20.0.0.100   ICMP Echo (ping) request  0.000097   20.0.0.100 -> 10.0.0.254   ICMP Echo (ping) reply

Thx for reading :)