How do I nat a request coming from inside my network to a public IP back to a device on my network?

Posted on 2005-05-03
Last Modified: 2010-04-17
I have a website that resides on my internal network, and is reached from the internet through natting on my router. However, when a machine inside my network tries to open the website with its public domain name, they cannot connect. How can I setup the proper NAT to let machines inside my network view the website while referencing its public IP.

For Example:
Internal webserver:
domainname: registered to
Existing Nat: ip nat source inside static tcp 80 80

What do I need to add so that when a machine on the same network as the webserver, eg host w/ip tries to connect to they are properly redirected.
Question by:jcc05
    LVL 41

    Expert Comment

    edit the hosts file on the local machines
    LVL 57

    Expert Comment

    by:Pete Long
    is your INTERNAL windows domain name

    if so just create an entry in DNS (or host files on each machine) that point

    www   to
    LVL 1

    Author Comment

    No, the domain is hosted by a third party and resides outside the network. I need to find a solution that is done at the routing level if possible.
    LVL 79

    Accepted Solution

    If it is a Cisco router you're out of luck. It simply can't  happen on the router. A local hosts file is the only way, or else an internal DNS server that resolves to private IP.
    What kind of router do you have?

    LVL 1

    Author Comment

    I am using a Cisco 2600 router.

    I also have a Cisco PIX firewall going into my network shortly that can also perform routing functions, would that be able to do it if the 2600 can't or is it a symptom of all cisco routing devices?
    LVL 79

    Expert Comment

    The PIX does have some "tricks" up its sleeves that the router does not.
    It can do "dns doctoring" and/or "outside nat" (alias), the IOS router simply has no equivelant..


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