how Do I Get the Client's Ip Instead Of My Firewall's?

Hi,

I'm migrating our website from our gateway/firewall over to a dedicated webserver that will sit behind the gateway. There are scripts on the website that do access control and display custom content depending on whether the client's IP address is external or internal (they're a lot of them, so rewriting them isn't feasible).

I got the gateway to forward HTTP traffic to the dedicated webserver. However, the CGI on the webserver all see the gateway's IP address when looking at the REMOTE_ADDR environment variable.

Is there a way to allow the webserver's CGI to see the client's or client's firewall's real IP address instead of our gateway's? As I mentioned before, there are a lot of scripts that need to do application level customization and access control based on whether the client's external or internal, so rewriting them all isn't a feasible solution for us.

Here's our setup.
Gateway:
SuSE Linux 8.1, using iptables (netfilter) for its firewall and routing

Webserver:
SuSe Linux 10
Apache HTTPD 2.2.3

Thanks!

That is a software issue, you could set up forwarding or use a transparent proxy like squid.