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Q: Cisco 1721 Cable Modem Setup Gateway NAT ( No Answer,   0 Comments )
Subject: Cisco 1721 Cable Modem Setup Gateway NAT
Category: Computers > Internet
Asked by: mstaffeld-ga
List Price: $11.00
Posted: 01 Nov 2006 13:17 PST
Expires: 01 Nov 2006 14:56 PST
Question ID: 779181
I?m trying to get a Cisco1721 WIC0 1ENET working behind a cable modem.
 I can ping the router from the inside, I can ping the cable gateway,
but I can?t seem to get the NAT working with the gateway.  I have a
few servers on the inside that I would like to NAT into them and a
workgroup that is on the inside that will use a certain IP.

I?ve taken a look at this with no avail:

Seems I?m still missing something.  I?ve tried both a crossover and a
straight through cable to the cable modem just in case.
My config looks like this so far:  

show run
Building configuration...

Current configuration : 1107 bytes
version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
hostname CORP_CABLE
enable secret 5 
enable password 
mmi polling-interval 60
no mmi auto-configure
no mmi pvc
mmi snmp-timeout 180
ip subnet-zero
no ip routing
ip dhcp excluded-address
ip dhcp pool CLIENT
   import all
   dns-server //My internal dns server.  
ip audit notify log
ip audit po max-events 100
interface Ethernet0 //This connects to the Cable Modem 
 ip address //One of the available public IPs
 ip nat outside
interface FastEthernet0 //Inside facing switches
 ip address
 ip nat inside
 no ip route-cache
 speed auto
ip nat inside source list 102 interface Ethernet0 overload
ip classless
ip route //This is my Gateway IP provided
from my ISP and is active.
ip http server
ip pim bidir-enable
access-list 102 permit ip any
ip nat inside source static tcp 80 80
//Forwards outside ip to inside http?
ip nat inside source static tcp 21 21
snmp-server community public RO
line con 0
line aux 0
line vty 0 4
no scheduler allocate

I can?t figure out how to get this working!  I have a diagram of what
I?m talking about here:

Please help me with a working config, this is stressing me out!
There is no answer at this time.

There are no comments at this time.

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