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Router Config Help - No Internet Access

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chamig

IS-IT--Management
Joined
Aug 23, 2005
Messages
5
Location
US
I am new to Cisco and configuring a new router at a new location. Below is a copy of my configuration. We have a T1 line and an Adtran. I have the router connected to the Adtran with a crossover cable through the FastEthernet 0/0 port. I have a computer connected to the router via a crossover cable and the FastEthernet 0/1 port. The computer has a static IP address of 172.20.145.2 255.255.255.248. From the router, I can ping all interfaces, the Adtran, website IP addresses, and the computer. From the computer, I can ping all interfaces on the router, but cannot ping the Adtran or any websites. I am sure it is something simple I'm missing. If anybody has any suggestions, I would grealy appreciate it. Thanks!

Current configuration : 1894 bytes
!
version 12.3
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname XXXXXXX
!
boot-start-marker
boot-end-marker
!
logging buffered 51200 warnings
enable secret 5 XXXXXXXXXXX
enable password XXXXXXXXXXX
!
username admin privilege 15 secret 5 XXXXXXXXXXXXX
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
no aaa new-model
ip subnet-zero
ip cef
!
!
!
!
ip domain name yourdomain.com
no ftp-server write-enable
!
password encryption aes
!
!
!
interface FastEthernet0/0
description $ETH-LAN$$ETH-SW-LAUNCH$$INTF-INFO-FE 0$
ip address 206.107.106.106 255.255.255.248
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 172.20.145.1 255.255.255.248
duplex auto
speed auto
!
ip classless
ip route 0.0.0.0 0.0.0.0 206.107.106.105
ip http server
ip http timeout-policy idle 600 life 86400 requests 10000
!
!
!
control-plane
!
banner login ^C
 
You haven't configured NAT!

Chris.

**********************
Chris A.C, CCNA, CCSA
**********************
 
WOW...that's Networking 101, huh? Thanks for the response!
 
after you have configured nat..you might want to try a straight cable instead of the cross between router and pc.

CCNA, CCNP..partly ;)
 
Ok, here's an update. I configured NAT and can access the internet through the router with a static ip adress of 172.20.145.2 - 172.20.145.6..any ip address above .6 cannot access the internet. Works the same using a crossover cable and a straight cable from PC to router. I set up NAT to overload to one IP address, the config is below...any help would be grealy appreciated!

interface FastEthernet0/0
description $ETH-LAN$$ETH-SW-LAUNCH$$INTF-INFO-FE 0$
ip address 206.107.106.106 255.255.255.248
ip nat outside
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 172.20.145.1 255.255.255.248
ip nat inside
duplex auto
speed auto
!
ip classless
ip route 0.0.0.0 0.0.0.0 206.107.106.105
ip http server
ip http timeout-policy idle 600 life 86400 requests 10000
ip nat pool test 206.107.106.106 206.107.106.106 prefix-length 29
ip nat inside source list 1 pool test overload
!
!
access-list 1 permit 172.20.145.0 0.0.0.255
 
any ip address above .6 cannot access the internet

Maybe that's because ...

Code:
interface FastEthernet0/1
 ip address 172.20.145.1 255.255.255.248

... you've got a /29 configured on the inside interface (255.255.255.248). Any address above 6 won't work unless you change the netmask.

Chris.



**********************
Chris A.C, CCNA, CCSA
**********************
 
Thanks Chris, I noticed that shortly after posting the message. Everything seems to be working great now. I am working on setting up VLANs and DHCP on the switch...and then on to the PIX... I'll try not to ask for too much help! Gotta love Cisco! Thanks again.
 
Hey I have a cisco 1721 router w/ver 12.4. Iam using it for a Voice over IP system with Covad as the carrier. I have a Cisco 2950 Catylst Switch. I can provide the configs for the router and switch if needed. Covad engineers said they can only support ver 12.3. I have 5 IP phones up and working; however I can't connect a P.C. and go to the internet. Any suggestions?
If you need more detail let me know roy@glscom.com
 
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