Set up NAT overload on 800

[x53gunner]

All,
I've tortured myself (and my Net Admin) long enough and he "forced" me to toss my old 3Com and let me borrow an 800 series to learn on/setup at home. I'm trying to set up NAT so I can use multiple machines on the same Cable modem
I've done a few hours of trying to make a go of it but I'm getting my @#% handed to me. Yes, I know nothing about Cisco except how to spell the name. I've tried this:

<

http://www.cisco.com/en/US/products...tion_guide_chapter09186a008007cdf0.html#4977>

And got this:

Router>configure terminal
^
% Invalid input detected at '^' marker.

Router>

I get that a lot. Especially when I use the help command and type the commands.

I tried this also:
Router>show ip nat translation

I get nothing (OK, I get the prompt).

I also downloaded this: <

http://www.tech-recipes.com/cisco_router_tips713.html>

and I'm lost.

Obviously I'm in way over my head. I'm a self taught computer geek and work in the IT shop so this shouldn't be too difficult or impossible to struggle through but I'm not going ANYWHERE. I must be missing some critical first inputs to get things going. Someone hook me up with some help

 

[ADB100]

You need to build the config in steps to understand how it all works, I will try so here goes....

1. Define your interface IP addresses and where they are

interface ethernet0
description Internal Network
ip address 192.168.1.254 255.255.255.0
!
interface ethernet1
description Connection to ISP
ip address negotiated


2. Create an Access List that covers your internal IP address space:

access-list 10 permit 192.168.1.0 0.0.0.255


3. Create your NAT translation and configure for PAT (Port Address Translation - Overload)

ip nat source list 10 interface ethernet1 overload


4. Define your inside and outside NAT interfaces:

interface ethernet0
ip nat inside
!
interface ethernet1
ip nat outside


That is it regarding the NAT configuration, obviously you need to configure your IP routes and any authentication on your ISP connection etc. I have an ADSL 800 and my Outside interface is Dialer1 so obviously the config of mine is slightly different.


Your initial problem is you have logged on to the router but you haven't entered enable mode. Before you can start to configure the router you must enter enable mode (type enable and press return). Cisco IOS has the concept of Privilege levels - logging on will by default give you level 0 privileges, configuration requires level 15.

HTH

Andy