Help needed. Ping working Nat Working no Internet services

[solpitz]

Hi all

my cisco Router C1113-8p has some issue. I had another Cisco router (1921 series) with similar configuration working mainly on the Nat and Dialler and was working succesfully.

I had set up 2 Dialler to my ISP one for VOIP and the other for internet access. 

Dialer 1 interface for Interenet access (has the issue for this post)

Dialer 2 for my IPPABX phone (Succesfully working - IPVPN link)

I had succesfully obtained Local IP from my NAT and DHCP for both services but the issue is with my internet access (Dialler 1). I am using 2 Vlans to curry the different DHCP Pools for my Internet access clients and the other for my IP Phone.

When hooking up to port interfaces linking me to my dialer 1 i can ping any web page. However i dont get any web session on my browser. 

can anyone assist or advise where i might made an error. 

see attached my configuration file. Note i had removed dialup credentials on it. 

[M02@rt37]

Hello @solpitz 

Do you configure MSS clamping on your dealer 1 interface ?

interface Dialer1
ip tcp adjust-mss 1452

[M02@rt37 · Accepted solution]

@solpitz 

When Dialer1 uses pppoe, its effective MTU drops to 1492 bytes.
If LAN clients still send 1500 byte packets and the router doesn’t adjust the tcp MSS, those large packets get fragmented or dropped. So HTTPS hangs while ping (small packets) still works...

[balaji.bandi]

We are still waiting for the attachment on this post, you can post the configuration in the post rather than an attachment to have a look.

interface Dialer1
 ip mtu 1492
 ip nat outside

[solpitz]

!
boot-start-marker
boot-end-marker
!
!
enable secret 9 $9$tKRRfU/A95iwHk$JDNV8b7IfwyVFieLpEHKqAjoL3lWH4/IOYzejboVoU.
enable password xxxxxxxx
!
no aaa new-model
!
!
!
!
!
!
!
ip host xxxxxxxxxxxxxxxxxxxxxxxxxxx
ip host sip.xxxxxxxxxxxxxxxxxxxxxxxxxxxx
ip name-server 2xxxxxxxxxxxxxxxxxx
ip domain name xxxxxxxx
ip dhcp excluded-address 192.168.10.1
ip dhcp excluded-address 192.168.40.1
!
ip dhcp pool Netaccess
network 192.168.40.0 255.255.255.0
default-router 192.168.40.1
domain-name xxxxxxxxxxx
dns-server 202.1.191.16 202.1.191.17
lease 9
!
ip dhcp pool IPPABX
network 10.199.95.0 255.255.255.240
domain-name xxxxxxxxxxx
dns-server 10.199.95.1
default-router 10.199.95.1
!
!
!
login on-success log
!
!
!
!
!
!
!
subscriber templating
multilink bundle-name authenticated
!
!
!
crypto pki trustpoint TP-self-signed-3926221875
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-3926221875
revocation-check none
rsakeypair TP-self-signed-3926221875
!
crypto pki trustpoint SLA-TrustPoint
enrollment pkcs12
revocation-check crl
!
!
crypto pki certificate chain TP-self-signed-3926221875
certificate self-signed 01
30820330 30820218 A0030201 02020101 300D0609 2A864886 F70D0101 05050030
31312F30 2D060355 04031326 494F532D 53656C66 2D536967 6E65642D 43657274
69666963 6174652D 33393236 32323138 3735301E 170D3235 31303133 30333135
31395A17 0D333531 30313330 33313531 395A3031 312F302D 06035504 03132649
4F532D53 656C662D 5369676E 65642D43 65727469 66696361 74652D33 39323632
32313837 35308201 22300D06 092A8648 86F70D01 01010500 0382010F 00308201
0A028201 01009E8E C77BCA8D E7529331 76D8A758 B69BC7E3 800357CD 05700E9C
BF823DA5 4C16F90D 50B35ED6 96FE024A 34EFC1C8 15958E4A 2D04A6BC C1D3A9C0
7B8F4F49 19851604 A0557266 7AA12CF2 9A73A412 0F7DF831 056F0987 5082BE9C
2CD9E176 AD0DB381 50515826 E3BAD754 2ED032B9 13592D5E 89BD5109 0AE91F75
D5DF11D1 7B3340D3 0D14F87F 1C8F54AD FAD371C9 FF770B9C BF948743 9A095AB9
616379CE E9662974 E4BA48E5 EF1385CB 210EE291 4AB28C62 91068110 368CC442
D7FB6EF6 EC14E872 D4D6326B A0F1B808 3E9D41B5 9D6F654B 61E7AD41 2291D1D6
D6702489 47E4D965 753F7086 BD95A20B 0A93F269 740A7363 2196286D 9F25BB3F
F8DB34E6 78C50203 010001A3 53305130 0F060355 1D130101 FF040530 030101FF
301F0603 551D2304 18301680 14080F4D 152E9A4D 05D057EB BAD63600 9CA53E65
9B301D06 03551D0E 04160414 080F4D15 2E9A4D05 D057EBBA D636009C A53E659B
300D0609 2A864886 F70D0101 05050003 82010100 0DF54A0C 144C9175 06DD857A
685460CA 77BC20F1 759C21A3 2D82F635 A3CF454B CC8F0D56 BAB1F1F7 9CB16D31
7507FC79 3696B967 8BF84FF3 5AFA74F9 A5A340FC E7493512 CF14FEDA 160D0A24
3A8AC448 0A096D49 FA535AEC 347F6A78 DF6AC2B3 58235BF1 56AAFD77 AAEEF098
E1FC4BF8 A6006EF2 6FD547B5 9D2DE0F8 9A07C049 4BB069AA C4CE1E0D A046CF04
1F09A1AE 639837AE 4FBB8B9F 92E04E5F 29AF8897 D1B587BA 0FE6BF7E 8D5F6E2C
2012DC1C C91D4C46 2218B8B7 8692D127 E88C7CC6 E57ECB45 E3B6904B D58023B9
54A95E6B 57DC9946 CD79E970 42C79F32 BCA128B9 FD78F38F 560F6CF7 1458593D
24941829 ECE4DE58 22693735 ABAE4F90 611BBC9A
quit
crypto pki certificate chain SLA-TrustPoint
certificate ca 01
30820321 30820209 A0030201 02020101 300D0609 2A864886 F70D0101 0B050030
32310E30 0C060355 040A1305 43697363 6F312030 1E060355 04031317 43697363
6F204C69 63656E73 696E6720 526F6F74 20434130 1E170D31 33303533 30313934
3834375A 170D3338 30353330 31393438 34375A30 32310E30 0C060355 040A1305
43697363 6F312030 1E060355 04031317 43697363 6F204C69 63656E73 696E6720
526F6F74 20434130 82012230 0D06092A 864886F7 0D010101 05000382 010F0030
82010A02 82010100 A6BCBD96 131E05F7 145EA72C 2CD686E6 17222EA1 F1EFF64D
CBB4C798 212AA147 C655D8D7 9471380D 8711441E 1AAF071A 9CAE6388 8A38E520
1C394D78 462EF239 C659F715 B98C0A59 5BBB5CBD 0CFEBEA3 700A8BF7 D8F256EE
4AA4E80D DB6FD1C9 60B1FD18 FFC69C96 6FA68957 A2617DE7 104FDC5F EA2956AC
7390A3EB 2B5436AD C847A2C5 DAB553EB 69A9A535 58E9F3E3 C0BD23CF 58BD7188
68E69491 20F320E7 948E71D7 AE3BCC84 F10684C7 4BC8E00F 539BA42B 42C68BB7
C7479096 B4CB2D62 EA2F505D C7B062A4 6811D95B E8250FC4 5D5D5FB8 8F27D191
C55F0D76 61F9A4CD 3D992327 A8BB03BD 4E6D7069 7CBADF8B DF5F4368 95135E44
DFC7C6CF 04DD7FD1 02030100 01A34230 40300E06 03551D0F 0101FF04 04030201
06300F06 03551D13 0101FF04 05300301 01FF301D 0603551D 0E041604 1449DC85
4B3D31E5 1B3E6A17 606AF333 3D3B4C73 E8300D06 092A8648 86F70D01 010B0500
03820101 00507F24 D3932A66 86025D9F E838AE5C 6D4DF6B0 49631C78 240DA905
604EDCDE FF4FED2B 77FC460E CD636FDB DD44681E 3A5673AB 9093D3B1 6C9E3D8B
D98987BF E40CBD9E 1AECA0C2 2189BB5C 8FA85686 CD98B646 5575B146 8DFC66A8
467A3DF4 4D565700 6ADF0F0D CF835015 3C04FF7C 21E878AC 11BA9CD2 55A9232C
7CA7B7E6 C1AF74F6 152E99B7 B1FCF9BB E973DE7F 5BDDEB86 C71E3B49 1765308B
5FB0DA06 B92AFE7F 494E8A9E 07B85737 F3A58BE1 1A48A229 C37C1E69 39F08678
80DDCD16 D6BACECA EEBC7CF9 8428787B 35202CDC 60E4616A B623CDBD 230E3AFB
418616A9 4093E049 4D10AB75 27E86F73 932E35B5 8862FDAE 0275156F 719BB2F0
D697DF7F 28
quit
!
!
license udi pid C1113-8P sn FCZ2609R6SN
memory free low-watermark processor 70642
!
diagnostic bootup level minimal
!
spanning-tree extend system-id
!
username xxxxxxxxxxx privilege 15 password 0 xxxxxxxxxxxxxx
!
redundancy
mode none
!
controller VDSL 0/2/0
!
!
vlan internal allocation policy ascending
!
!
!
!
!
!
interface GigabitEthernet0/0/0
no ip address
negotiation auto
pppoe enable group global
pppoe-client dial-pool-number 2
pppoe-client dial-pool-number 1
!
interface GigabitEthernet0/1/0
description --LAN--
switchport access vlan 10
!
interface GigabitEthernet0/1/1
!
interface GigabitEthernet0/1/2
!
interface GigabitEthernet0/1/3
!
interface GigabitEthernet0/1/4
!
interface GigabitEthernet0/1/5
!
interface GigabitEthernet0/1/6
description IPPABX_Port
switchport access vlan 20
switchport mode access
!
interface GigabitEthernet0/1/7
!
interface ATM0/2/0
no ip address
shutdown
atm oversubscribe factor 2
!
interface Ethernet0/2/0
no ip address
shutdown
no negotiation auto
!
interface Vlan1
no ip address
shutdown
!
interface Vlan10
ip address 192.168.40.1 255.255.255.0
ip nat inside
!
interface Vlan20
description IPPABX
ip address 10.199.95.1 255.255.255.240
!
interface Dialer1
mtu 1492
ip address negotiated
no ip redirects
ip mtu 1452
encapsulation ppp
ip tcp adjust-mss 1412
dialer pool 1
dialer idle-timeout 0
dialer persistent
dialer-group 1
ppp mtu adaptive
ppp authentication chap pap callin
ppp chap hostname xxxxxxxxxxxxxxx
ppp chap password 0 xxxxxxxxxxxxxxx
!
interface Dialer2
mtu 1492
ip address negotiated
no ip redirects
ip mtu 1452
ip nat outside
encapsulation ppp
ip tcp adjust-mss 1412
dialer pool 2
dialer idle-timeout 0
dialer persistent
dialer-group 2
ppp mtu adaptive
ppp authentication chap pap callin
ppp chap hostname xxxxxxxxxxxxxxxxxxxxxxxxxx
ppp chap password 0 xxxxxxxxxxxxxxxxx
!
ip http server
ip http authentication local
ip http secure-server
ip http secure-trustpoint TP-self-signed-3474261517
ip forward-protocol nd
ip dns server
ip nat inside source list 1 interface Dialer2 overload
ip route 0.0.0.0 0.0.0.0 Dialer1
ip route 202.1.184.192 255.255.255.248 Dialer2
!
!
ip access-list extended remote-access
10 permit ip host 202.1.184.135 any
!
ip access-list standard 1
10 permit 192.168.40.0 0.0.0.255
!
!
!
control-plane
!
!
line con 0
transport input none
stopbits 1
line vty 0 4
password xxxxxx
login
transport input ssh
line vty 5 14
password xxxxxxx
login
transport input ssh
!
call-home
! If contact email address in call-home is configured as sch-smart-licensing@cisco.com
! the email address configured in Cisco Smart License Portal will be used as contact email address to send SCH notifications.
contact-email-addr sch-smart-licensing@cisco.com
profile "CiscoTAC-1"
active
destination transport-method http
!
!
!
!
!
!
end

[balaji.bandi]

interface Dialer1
mtu 1492
ip address negotiated
no ip redirects
ip mtu 1452
encapsulation ppp
ip tcp adjust-mss 1412
dialer pool 1
dialer idle-timeout 0
dialer persistent
dialer-group 1
ppp mtu adaptive
ppp authentication chap pap callin
ppp chap hostname xxxxxxxxxxxxxxx
ppp chap password 0 xxxxxxxxxxxxxxx
!
interface Dialer2
mtu 1492
ip address negotiated
no ip redirects
ip mtu 1452
ip nat outside
encapsulation ppp
ip tcp adjust-mss 1412
dialer pool 2
dialer idle-timeout 0
dialer persistent
dialer-group 2
ppp mtu adaptive
ppp authentication chap pap callin
ppp chap hostname xxxxxxxxxxxxxxxxxxxxxxxxxx
ppp chap password 0 xxxxxxxxxxxxxxxxx
!

try 1492 or 1452 and see that works

[solpitz]

hi thanks for the feedback

I just corrected my errors was on the interface dialer for nat overload. also MTU adjustment had my session working 

[M02@rt37]

Great!

Thanks for your feedback too. Have a nice day.