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We use a software on our windows 2008 server that regularly needs to connect to a licensing server. For budget reasons, we don't have a public fixed IP address. The problem is that the licensing website will disable our software license if the incoming IP address is not always the same.

A possible solution would be to use one of our Amazon EC2 windows instance that has a public fixed IP address, as a kind of proxy or router, but only for the website so that this website would always 'see' the same IP address.

So we should configure our internal server to use amazon server as a gateway for outgoing traffic to The amazon server (windows 2008 r2) should accept and forward such traffic. Any idea on how to configure such features?

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Would you mind telling us what software requires this? Unless it's some type of law enforcement software, I'd be hard-pressed to imagine that someone's licensing scheme is based on IP address. – GregD Apr 26 '11 at 13:39
I don't see any reason for this at all, personally. I don't know why software for LEOs would be an exception. You public IP address means squat, outside of the context of a single IP transmission. You could be on DHCP and have your lease renew. You could be on BGP and failover. Your fiber connection could get cut and you're on DSL or T1 until it's fixed. You could change ISPs, for heaven's sake. That's some shitty licensing scheme right there. – mfinni Apr 26 '11 at 20:05
Suggestion - ask your vendor, quite pointedly, why they would decide to invalidate your license when the DHCP lease from your ISP expires and you get a new IP. – mfinni Apr 26 '11 at 20:06
Thanks all for your comments. The software is Ahsay's online backup system. They explain they use the incoming IP address as a proof of valid/purchased license... they kindly suggested to contact them to 'relax' the license if there is any change in the IP address, but I can't do this every day! So the question here is not to ask them to change their software... – Thomas Apr 27 '11 at 16:14

I would suggest configure it on the proxy/firewall level. Basically, requests that sent to specific site will be forwarded to the Amazon EC2, for example, and you would need to configure RRAS on the server to forward the request from your IP to the licensing site. In essence, it's possible to do using squid on the internal network and IPTABLES on the server in Amazon EC2, or similar, service.

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thanks for your answer vick. but afaik squid and iptables are linux related stuff, right? here we're talking about 2 windows servers (local and amazon) – Thomas Apr 27 '11 at 16:16
@Thomas, that's correct, however you can easily implement this solution setting up LINUX boxes IN FRONT of the Windows servers. – Vick Vega Apr 27 '11 at 16:39

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