FireWall-1 FAQ: NAT Based on Service With Only One Legal IP
Please note: This content was from when I was operating my FireWall-1 FAQ site, which I stopped operating in August 2005. For some reason people still have links to this stuff on the Internet that people are still clicking on.
I am making this information available again AS IS. Given how old this information is, it is likely wildly inaccurate. I have no plans to update this information.
If you're still running versions of Check Point VPN-1/FireWall-1 where this information is still relevant to you, do yourself a favor and upgrade to a more recent release. If you happen to be running a current release and the information is useful, it's by happenstance :)
In the NG release, it is possible to do this because NAT can occur before routing. In the Global Properties, in the NAT section, make sure “Perform destination translation on the client side” is checked. Then you can create NAT rules similar to the following: