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Newbie question !

We ordered a new external IP from our ISP. our service provider supplied us with private IP addresses (range) and NAT address.

however the external IP is still the same, how i can setup the server to use the exact external IP ?

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What kind of service is this? Did they provide you hardware? It's a bit confusing trying to figure out whether our need a static NAT through a firewall or whether your machines will have some kind of direct/bridged connection to the public Internet. – SpacemanSpiff May 22 '11 at 20:43
@SpacemanSpiff : the NAT provided to me is like 1.80.*.**. all the organization connections map to a single external IP. we have a new server where which we need to point to another external IP using this NAT address and private IP ranges that our ISP assigned to the new external IP. sorry for the confusion ! I hope i made myself clear. – HeoQue May 22 '11 at 21:11
This is still not very clear to me. Your ISP cannot "provide" you with private IP ranges, they are yours to choose from freely. Why don't you post the actual addresses and ranges? – wolfgangsz May 22 '11 at 23:09

Firstly I'm assuming your server is a hosted server and your ISP/Service Provider has provided you with an additional IP address (private and NAT'd public address) for assignment to your server.

Assuming your server is currently assigned IP address X1 which maps to the external public address Y1. All of your traffic to the internet is appearing to come from Y1. Is this correct?

Secondly you now have been assigned addresses X2 and Y2 and you want your server traffic to appear to come from Y2 now. If this is correct then you can do one of the following:

  1. If you don't care about X1 or Y1 anymore, then change the server Local Area Connection IP address from X1 to X2. Note you won't be able to access your server on X1 or Y1 again.

  2. Add X2 as an additional address on the Local Area Connection and change your routing tables to route out via the X2 interface. But this gets tricky.

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This is the situation ! I think i will go for option 2. how i can achieve that in Windows 2008 ? Also i tried option #1, it didn't work for me, when i check my public address it is still Y1 though I'm using X2 , that's why i thought it has something to do with setting up the NAT – HeoQue May 23 '11 at 10:40

Why don't you tell us exactly what you are trying to do, for example: We are trying to get web traffic through our x-brand firewall to talk to our server at IP address

I am with wolfgangz, you may connect to some company, which provides a service, and therefore has you use a particular subnet, but if not, you can pick any non-routable subnet internally. It is not provided to you.

Your question makes no sense: "however the external IP is still the same, how i can setup the server to use the exact external IP"

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ok, I have been given the following : You can use address: NAT address: I have been told that using this settings i will be able to use the new external IP – HeoQue May 23 '11 at 8:02

if you own the firewall/router, or you have the admin password to the same then you can put any private ip you like. The router translates the addresses when traffic goes out to the internet.

What they've supplied is rather odd - with a subnet mask of Its legal but odd.

I would guess that is the ip of your router. Try setting up a PC with IP subnet mask default gateway

you should be able to ping the router ( and, if not then we don't have the correct details.

I'd ask them to change the internal address and subnet mask to match your current one - or change it yourself.

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