02-08-2012 06:46 AM - edited 03-07-2019 04:48 AM
I have a Cisco 3620 router and I am trying to get internet access. My isp is comcast. All modem lights seem to be operational. But I do not have internet access. I can ping anything other then the router and I am on a home network.
I have attached a config file. Please note I am a novice with cisco routers.
02-16-2012 07:03 AM
Hi Ray,
mac-address 000b.46cc.8fc1 (This is the mac addr of the E0/0 interface card)
no need to put this command on eth0/0 as it is already its MAC address and furthermore this interface is not connected to the modem.It won't do any bad but it is unnecessary.
no ip route-cache
Don't enter this command, renable it with either ip cef global command or ip route-cache cef interface command and verify with sh cef interface command.
Your arp requests for the PC gateway( 192.168.3.1) are not replied by the router, can you try to purge the cache with arp -d * command on the PC and do a ping 192.168.3.1 and then see if you get the correct mapping in the cache.
But I would like to have the wireshark capture when PC connected directly to modem.
Regards.
Alain
02-16-2012 01:54 PM
I removed the mac address from E0/0. And removed the no ip route.
(Note that "no ip route-cache" and "ip address dhcp" commands were added from the Cisco config link from about. That's why they were in the config.)
New wireshark file add. Info captured while pc was connected to the cable modem this time, and all pings were fine.
And updated config file attached also. I could not remove the " no ip mroute-cache" command.
Thanks Ray
02-16-2012 02:34 PM
Hi Ray,
Why did you remove the ip address dhcp command on eth0/1 ? reenter this command
if you don't get the default-gateway ( sh ip route) then try this :
ip route 0.0.0.0 0.0.0.0 dhcp
let us know.
Regards.
Alain
02-16-2012 09:45 PM
Hi Ray,
I just want to add something else to all the good advise you get from Alain.
This things needs to be performed in certain order, otherwise it won't work.
After you have changed mac address on router to match the mac on pc, and before you connect router to modem, make sure that you use a pin to reset modem to factory defaults, should have a small opening at the back.
After the modem is reset to factory defaults, plug in the router and no PC connected to router.
Eugen
02-17-2012 06:12 AM
Made all corrections, reset modem to defaults and still no internet.
Ran (sh ip route) and only e0/0 is returned. Pinged to router from pc is fine but ping 8.8.8.8 says no destination,(ping 8.8.8.8 from both pc and router).
When I tried to run (ip route 0.0.0.0 0.0.0.0 dhcp) it return, "Invalid input detected at dhcp". When I run
ip route 0.0.0.0 0.0.0.0 ?, there is no dhcp option.
Ray
02-17-2012 06:28 AM
Hi,
so the router is still not getting any IP from DHCP.
can you do a debug dhcp client on the router and post output.
Regards.
Alain.
02-17-2012 01:11 PM
Alain,
I ran the following command:
debug ip dhcp server packets
And it only returned the following:
DHCPD: checking for expired leases.
That staement was rturned about every 5 minutes.
Ray
02-17-2012 01:38 PM
02-17-2012 04:20 PM
Hi Ray,
Just a quick question.
Do you have dhcp server enabled on the router?
02-22-2012 07:11 AM
eugne,
I ran the "service dhcp" command and still no internet and can't ping 8.8.8.8
Below is my config:
version 12.2
no parser cache
no service pad
no service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname ccefl
!
logging buffered 10000 debugging
enable password cisco
!
username ray privilege 15 password 0 cisco
username all
ip subnet-zero
ip cef
!
!
ip name-server 208.67.222.222
ip name-server 208.67.220.220
ip dhcp excluded-address 192.168.3.1
ip dhcp excluded-address 192.168.3.2
ip dhcp excluded-address 192.168.3.10
ip dhcp excluded-address 192.168.3.3
ip dhcp excluded-address 192.168.3.4
ip dhcp excluded-address 192.168.3.5
ip dhcp excluded-address 192.168.3.6
ip dhcp excluded-address 192.168.3.7
ip dhcp excluded-address 192.168.3.8
ip dhcp excluded-address 192.168.3.9
!
ip dhcp pool lan_ccefl
import all
network 192.168.3.0 255.255.255.0
dns-server 208.67.222.222
default-router 192.168.3.1
lease 3
!
call rsvp-sync
!
!
!
!
!
!
!
!
interface Tunnel1
no ip address
!
interface Ethernet0/0
ip address 192.168.3.1 255.255.255.0
ip nat inside
no ip mroute-cache
full-duplex
no cdp enable
!
interface Ethernet0/1
description exit
mac-address 0011.e398.dcc6
ip address 192.168.100.1 255.255.255.0
ip nat outside
no ip mroute-cache
full-duplex
no cdp enable
!
ip nat inside source list 1 interface Ethernet0/1 overload
ip classless
ip http server
ip http authentication local
ip http path flash
!
access-list 1 permit 192.168.3.0 0.0.0.255
access-list 199 permit icmp any any
no cdp run
!
dial-peer cor custom
!
!
!
!
line con 0
line aux 0
line vty 0 3
password cisco
login local
line vty 4
password cisco
login local
transport input telnet
!
end
02-22-2012 03:18 PM
Hi Ray,
I may ask a silly question..
To what port in the modem are connecting your router? Also can you disable dhcp server on the router until you have your internet working "no dhcp server". You can give a static ip to the PC and LAN interface for testing. Can you post another show run output after you disable dhcp
Regards
Eugen
02-22-2012 03:33 PM
PC already has a static IP address.
"To what port in the modem are connecting your router?" It's connected to the rj-45 port, it's the only option.
Will do a sh run and disable dchp server next try.
02-22-2012 03:58 PM
Thats good. Can you also post the output of "sh version".
02-24-2012 05:33 AM
eugen,
I had to use the " no service dhcp" command, the "no dhcp server" did not work. And below are the two outputs of sh run and sh version:
Building configuration...
Current configuration : 1669 bytes
!
version 12.2
no parser cache
no service pad
no service timestamps debug uptime
service timestamps log uptime
no service password-encryption
no service dhcp
!
hostname ccefl
!
logging buffered 10000 debugging
enable password cisco
!
username ray privilege 15 password 0 cisco
username all
ip subnet-zero
ip cef
!
!
ip name-server 208.67.222.222
ip name-server 208.67.220.220
ip dhcp excluded-address 192.168.3.1
ip dhcp excluded-address 192.168.3.2
ip dhcp excluded-address 192.168.3.10
ip dhcp excluded-address 192.168.3.3
ip dhcp excluded-address 192.168.3.4
ip dhcp excluded-address 192.168.3.5
ip dhcp excluded-address 192.168.3.6
ip dhcp excluded-address 192.168.3.7
ip dhcp excluded-address 192.168.3.8
ip dhcp excluded-address 192.168.3.9
!
ip dhcp pool lan_ccefl
import all
network 192.168.3.0 255.255.255.0
default-router 192.168.3.1
dns-server 208.67.222.222
lease 3
!
call rsvp-sync
!
!
!
!
!
!
!
!
interface Tunnel1
no ip address
!
interface Ethernet0/0
ip address 192.168.3.1 255.255.255.0
ip nat inside
no ip mroute-cache
full-duplex
no cdp enable
!
interface Ethernet0/1
description exit
mac-address 0011.e398.dcc6
ip address dhcp
ip nat outside
no ip mroute-cache
full-duplex
no cdp enable
!
ip nat inside source list 1 interface Ethernet0/1 overload
ip classless
ip route 0.0.0.0 0.0.0.0 Ethernet0/1
ip http server
ip http authentication local
ip http path flash
!
access-list 1 permit 192.168.3.0 0.0.0.255
access-list 199 permit icmp any any
no cdp run
!
dial-peer cor custom
!
!
!
!
line con 0
line aux 0
line vty 0 3
password cisco
login local
line vty 4
password cisco
login local
transport input telnet
!
end
ccefl#sh version
Cisco Internetwork Operating System Software
IOS (tm) 3600 Software (C3640-IS-M), Version 12.2(13b)M2, RELEASE SOFTWARE (fc1)
TAC Support: http://www.cisco.com/tac
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Fri 08-Aug-03 18:39 by yiyan
Image text-base: 0x60008930, data-base: 0x61122000
ROM: System Bootstrap, Version 11.1(20)AA2, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)
ccefl uptime is 13 minutes
System returned to ROM by power-on
System image file is "flash:Z12213BM2.POO"
cisco 3640 (R4700) processor (revision 0x00) with 126976K/4096K bytes of memory.
Processor board ID 29545610
R4700 CPU at 100Mhz, Implementation 33, Rev 1.0
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
2 Ethernet/IEEE 802.3 interface(s)
DRAM configuration is 64 bits wide with parity disabled.
125K bytes of non-volatile configuration memory.
32768K bytes of processor board System flash (Read/Write)
Configuration register is 0x2102
02-29-2012 07:42 AM
eugen,
Congrats on passing your test.
Ray
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