Need help connecting Cable Modem to 1841 Router

LeftyFretz

I've been attempting to connect an 1841 router to a cable modem. I can ping the router from my pc but unable to connect. Does the config below look correct?


Current configuration : 1118 bytes
!
version 12.4...

service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname R1
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$3KSo$mJH6DOvBi3wie0hSXSFkg0
!
no aaa new-model
ip cef
!
!
no ip dhcp use vrf connected
ip dhcp excluded-address 192.168.1.1 192.168.1.30
!
ip dhcp pool insideDHCP
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 209.18.47.62 209.18.47.61
!
interface FastEthernet0/0
description Facing my LAN
ip address 192.168.1.1 255.255.255.0
ip nat inside
ip virtual-reassembly
duplex auto
speed auto

DCD

Where is the other interface? Do a "shpw ip interface brief" and you will need a default route since you are not using a routing protocol.

clarson

well looks like your whole config file isn't there. But, that is a good start.

what you need to do is connect one of the 1841's fastethernet ports to your cable modem, fe0/1
you need to configure fe0/1 to get it's ip address via dhcp and be outside nat
interface FastEthernet0/1
ip address dhcp
ip nat outside

setup nat
ip nat inside source list 22 interface FastEthernet0/1 overload
!
access-list 22 permit any

configure a default static route
ip route 0.0.0.0 0.0.0.0 192.168.xx.1 <-- cable modems ip address

propagate default route to your other routers, this case using rip
default-information originate

Hondabuff

Something down and dirty like this.

Router#sho run
Building configuration...




Current configuration : 999 bytes

!

version 12.4

no service timestamps log datetime msec

no service timestamps debug datetime msec

no service password-encryption

!

hostname Router

!

!

!

!

ip dhcp excluded-address 192.168.100.1 192.168.100.5

!

ip dhcp pool INTERNAL-DHCP

network 192.168.100.0 255.255.255.0

default-router 192.168.100.1

dns-server 8.8.8.8

!

!

!

ip cef

no ipv6 cef

!

!

!

!

!

!

!

!

!

!

!

!

spanning-tree mode pvst

!

!

!

!

!

!

interface FastEthernet0/0

description LAN INTERNAL

ip address 192.168.100.1 255.255.255.0

ip nat inside

duplex auto

speed auto

!

interface FastEthernet0/1

description WAN to Modem

ip address 192.168.1.2 255.255.255.0

ip nat outside

duplex auto

speed auto

!

interface Vlan1

no ip address

shutdown

!

ip nat inside source list NAT interface FastEthernet0/1 overload

ip classless

ip route 0.0.0.0 0.0.0.0 192.168.1.1

!

ip flow-export version 9

!

!

ip access-list extended NAT

permit ip 192.168.100.0 0.0.0.255 any

!

!

!

!

!

line con 0

!

line aux 0

!

line vty 0 4

login

!

!

!

end

MAC_Addy

The modem you're using, is it provided with a static or DHCP address? If it's DHCP, set the router port to DHCP. Then just use a static route to forward 0.0.0.0 out of the LAN to WAN port.