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I need the ability to make all of my outbound traffic to IP address a.b.c.d route to IP address e.f.g.h.

Here's the problem, I'm being handed a URL from a server. This URL contains dotted IP addresses (please don't tell me to change the application). The URL I'm being handed is for a service that resides within a firewalled environment. Unfortunately, I've been given the internal IP address (for good reason) and as such my machine cannot access that address directly (e.g. However, we have setup a public address ( that is NAT'd on the router to the internal address (

I don't want to throw a piece of hardware between my machine and the router. All I want to know is if it is possible to use the ip address on my machine and have my machine NAT that into as part of the routing. This is windows 2003.

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In the end I was able to solve my issue. The target address was not directly routable from my server. So, I setup a loopback adapter on the machine and assigned the target IP address to the loopback adapter. Then I installed passport to forward my data and connections from the loopback to the public address. – Ajaxx Sep 29 '09 at 19:59

Its a pity that it's using an IP address, because otherwise you could just change an entry in your HOSTS file to re-map the FQND.

Anyway, I don't know of any way in Windows 2003 to do what you want, but there's only one way you can do this, and that's to modify the packet at some point along its path for the header to read - otherwise, even if you could somehow force the packet to the other address it would have the original header and the device at the other end would just drop it.

What you will need is some device, in-line with your machine, that does packet inspection on each and every TCP packet that leaves your computer. It needs to check the destination and modify it if it matches a certain pattern. I am sure that some such tool exists in a hackers toolkit somewhere, but I've no idea what it might be.

The other option is to deliberately use ARP poisoning to re-map the MAC address of to, and then set up the other device to listen on both IP addresses on its WAN interface (often called Virtual IPs).

Hope this provides some help!

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