09-24-2013 02:13 AM - edited 03-04-2019 09:07 PM
Hey everyone,
I have an issue with my cisco router 1921. I configured two VLANs (192.168.0.0 & 192.168.1.0) and a pppoe connection with my internet provider. The routing between the two VLAN is fine and the pppoe over fiber as well.
The thing is I can ping an internet website from the router interface but can not from a computer on the LAN. I think it is an issue with NAT/PAT or access list. Hereafter you will find the configuration of the router.
Does someone can help me ?
GVANE01#show running-config
Building configuration...
Current configuration : 5268 bytes
!
! Last configuration change at 10:24:34 GMT Thu Sep 19 2013 by admin
! NVRAM config last updated at 10:26:47 GMT Thu Sep 19 2013 by admin
! NVRAM config last updated at 10:26:47 GMT Thu Sep 19 2013 by admin
version 15.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname GVANE01
!
boot-start-marker
boot-end-marker
!
!
logging buffered 51200 warnings
enable secret 4 O8gVxDZkPDpDZ8jTgGXAY2O0eE0ZpmGM6gPQMFkOCaw
enable password xxxxxxx
!
no aaa new-model
clock timezone GMT 1 0
clock summer-time GMT recurring
!
ip cef
!
!
!
ip dhcp excluded-address 10.10.10.1
ip dhcp excluded-address 192.168.0.1 192.168.0.99
!
ip dhcp pool ccp-pool
import all
network 10.10.10.0 255.255.255.248
default-router 10.10.10.1
lease 0 2
!
ip dhcp pool DHCP_GREENWICH
import all
network 192.168.0.0 255.255.255.0
dns-server 195.186.1.162 195.186.4.162
default-router 192.168.0.254
!
!
!
ip domain name yourdomain.com
ip name-server 195.186.1.162
ip name-server 195.186.4.162
no ipv6 cef
multilink bundle-name authenticated
!
vpdn enable
!
vpdn-group Swisscomm
!
!
template Virtual-Access1
!
!
crypto pki trustpoint TP-self-signed-98202878
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-98202878
revocation-check none
rsakeypair TP-self-signed-98202878
!
!
crypto pki certificate chain TP-self-signed-98202878
certificate self-signed 01
30820227 30820190 A0030201 02020101 300D0609 2A864886 F70D0101 05050030
2F312D30 2B060355 04031324 494F532D 53656C66 2D536967 6E65642D 43657274
69666963 6174652D 39383230 32383738 301E170D 31333036 31323137 30303533
5A170D32 30303130 31303030 3030305A 302F312D 302B0603 55040313 24494F53
2D53656C 662D5369 676E6564 2D436572 74696669 63617465 2D393832 30323837
3830819F 300D0609 2A864886 F70D0101 01050003 818D0030 81890281 8100D506
92C9EA0B 7C5B4ABD D0D949C4 4B44C378 0A3804A6 13EDD1DD A086B242 E2AD293B
57E13770 27150AD1 9AD2E4A4 02DCAF50 D3FC9A0D A07AAA85 997350FD AFB66AA6
2AF7805F 74C3A9EC 9BA47A11 6D1930A8 318C68AC 4D6328B4 74D30054 0AEFF5B0
8246B3A0 8662CE0B 32EE7258 0DCBAEB4 61EB5D90 11581DE6 CA0BEB7A 9DC90203
010001A3 53305130 0F060355 1D130101 FF040530 030101FF 301F0603 551D2304
18301680 14272741 32B671FF 353902C8 DAE12FA7 13800772 32301D06 03551D0E
04160414 27274132 B671FF35 3902C8DA E12FA713 80077232 300D0609 2A864886
F70D0101 05050003 81810067 89A94BA9 DCB26B1E 1009F68B EBCC61FE AAC3AC68
63CD2E46 5082F976 D470F5E6 9031B21A 9C03E93B AF956157 5F0117D6 9CF372F0
47425C0B BBB11E81 89F1AD58 F37E7EEB 6C3DB780 5FC80888 159B6E9C 56BD388F
EB6C9DB9 9C677B72 A1D216EF 91D40B11 422F2378 0C211171 6C2B9AE9 4BCC1762
E8FC4B69 E8198EF0 51B54B
quit
license udi pid CISCO1921/K9 sn FCZ1724C2ZC
!
!
username admin privilege 15 secret 4 O8gVxDZkPDpDZ8jTgGXAY2O0eE0ZpmGM6gPQMFkOCaw
!
!
!
!
!
!
interface Embedded-Service-Engine0/0
no ip address
shutdown
!
interface GigabitEthernet0/0
description Fiber Swisscomm
mtu 1452
no ip address
duplex auto
speed auto
pppoe enable group global
pppoe-client dial-pool-number 1
no mop enabled
!
interface GigabitEthernet0/1
description LAN-Greenwich
no ip address
duplex auto
speed auto
no mop enabled
!
interface GigabitEthernet0/1.1
description LAN Greenwich
encapsulation dot1Q 1 native
ip address 192.168.0.254 255.255.255.0
ip nat inside
ip virtual-reassembly in
!
interface GigabitEthernet0/1.2
description IPC
encapsulation dot1Q 2
ip address 192.168.1.254 255.255.255.0
!
interface Dialer1
mtu 1492
ip address negotiated
ip nat outside
ip virtual-reassembly in
encapsulation ppp
dialer pool 1
dialer-group 1
ppp authentication pap callin
ppp chap hostname xxxxxxxxxxxxxxxxxxxx
ppp chap password 0 xxxxxxxxx
ppp pap sent-username xxxxxxxxxxxxxxxxx password 0 xxxxxxxx
!
ip forward-protocol nd
!
ip http server
ip http access-class 23
ip http authentication local
ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
!
ip nat inside source list 1 interface Dialer1 overload
ip nat inside source list DSL_ACCESSLIST interface Dialer1 overload
ip route 0.0.0.0 0.0.0.0 Dialer1
ip route 192.168.0.0 255.255.255.0 GigabitEthernet0/1.1
ip route 192.168.1.0 255.255.255.0 GigabitEthernet0/1.2
!
ip access-list extended DSL_ACCESSLIST
permit ip 10.10.10.0 0.0.0.255 any
!
!
!
snmp-server community Greenwich RO
snmp-server community public RO
snmp-server enable traps entity-sensor threshold
access-list 10 permit 192.168.0.0 0.0.0.255
access-list 23 permit 10.10.10.0 0.0.0.7
access-list 100 permit ip 10.10.10.0 0.0.0.255 any
access-list 101 permit tcp any any
access-list 101 permit udp any any
access-list 101 permit icmp any any
!
control-plane
!
!
!
line con 0
login local
line aux 0
line 2
no activation-character
no exec
transport preferred none
transport input all
transport output pad telnet rlogin lapb-ta mop udptn v120 ssh
stopbits 1
line vty 0 4
access-class 23 in
privilege level 15
password xxxxxxxx
login local
transport input telnet ssh
line vty 5 15
access-class 23 in
privilege level 15
password xxxxxxx
login local
transport input telnet ssh
!
scheduler allocate 20000 1000
ntp update-calendar
ntp server ch.pool.ntp.org
!
end
Solved! Go to Solution.
09-24-2013 03:33 AM
Hi Sylvain,
If you want to NAT also LAN 192.168.1.0 /24 then you are missing ip nat inside statement
interface GigabitEthernet0/1.1
description LAN Greenwich
encapsulation dot1Q 1 native
ip address 192.168.0.254 255.255.255.0
ip nat inside
ip virtual-reassembly in
!
interface GigabitEthernet0/1.2
description IPC
encapsulation dot1Q 2
ip address 192.168.1.254 255.255.255.0
???
Regarding the ip nat source list: You have defined 2 statements.
ip nat inside source list 1 interface Dialer1 overload
ip nat inside source list DSL_ACCESSLIST interface Dialer1 overload
So, if you want to translate also the 192.168.1.0 /24, add it into access-list with 192.168.0.0 /24.
Change
ip nat inside source list 1 interface Dialer1 overload
to
ip nat inside source list 10 interface Dialer1 overload
or cerate access-list 1 with permit 192.168.0.0 /24.
Best regards,
Jan
09-24-2013 05:08 AM
Hi,
interface g0/0
no mtu 1452
int g0/1.1
ip tcp adjust-mss 1452
Regards
Alain
09-24-2013 03:33 AM
Hi Sylvain,
If you want to NAT also LAN 192.168.1.0 /24 then you are missing ip nat inside statement
interface GigabitEthernet0/1.1
description LAN Greenwich
encapsulation dot1Q 1 native
ip address 192.168.0.254 255.255.255.0
ip nat inside
ip virtual-reassembly in
!
interface GigabitEthernet0/1.2
description IPC
encapsulation dot1Q 2
ip address 192.168.1.254 255.255.255.0
???
Regarding the ip nat source list: You have defined 2 statements.
ip nat inside source list 1 interface Dialer1 overload
ip nat inside source list DSL_ACCESSLIST interface Dialer1 overload
So, if you want to translate also the 192.168.1.0 /24, add it into access-list with 192.168.0.0 /24.
Change
ip nat inside source list 1 interface Dialer1 overload
to
ip nat inside source list 10 interface Dialer1 overload
or cerate access-list 1 with permit 192.168.0.0 /24.
Best regards,
Jan
09-24-2013 03:53 AM
Thanks a lot Jan! It works, I can ping from a PC from the network 192.168.0.0/24 (and btw understand better the link between access-list and source list...).
But there is still something wrong... I can not access a web page from a browser. Do you know why? Can it be something with MTU ?
09-24-2013 05:08 AM
Hi,
interface g0/0
no mtu 1452
int g0/1.1
ip tcp adjust-mss 1452
Regards
Alain
09-24-2013 05:27 AM
Hey,
It is much better, thanks! I can reach all the websites now but I still have this message when I activate debug ppp negotiation :
Sep 24 12:24:21.910: Vi2 PPP: Outbound cdp packet dropped, NCP not negotiated
Do you know why?
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