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New Member

1720 and NAT

I will start by saying that I am completely new to the Cisco IOS. Now, with that said here is my situation. We are moving offices and upgrading to a full T1 in the process. This requires, of course, a new router and with that new configurations!!!

I am trying to overload a single external IP with the pool of our internal ips (192.168 block).

I have been using the configmaker to set up dummy configs so that I can see how the IOS commands are supposed to be input. While doing this I have found that I cannot create the NAT environment that I would like... at least not with my current level of knowledge.

I want this: - =

I need all internal IP's to map to that single external (I believe cisco calls this overload). My problem seems to be that I cannot force this type dynamic NAT using the cisco config maker. I can do static mapping no problem: =

but cannot get: =

If anyone could point me in the correct direction I would be disgustingly grateful :)


New Member

Re: 1720 and NAT



ip nat inside source list NETWORK interface Ethernet0/0 overload

Define an standarded named access list NETWORK with a permit statement of

Apply ip nat inside to the 192.168 interfaces.

Apply ip nat outside to the 66.XX.YY.ZZ interface.

Cisco Employee

Re: 1720 and NAT


Here is my reply with respect to ConfigMaker.

You can configure what you have mentioned using ConfigMaker.

Just go to the Connection properties for which you need to configure NAT. Go to "NAT" Tab.

You have an option called

"Use WAN Interface Address for dynamic source address translation". You can check it. This will solve your problem. You can find the respective configuration getting deievred in the IOS Configuration.

Please let me know if your query is something different.


Ravikumar Eswaran.

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