I have a lan of maybe 20 - 30 computers, and a Windows server 2003 server on hand (I can also run any x86 Linux distro).
What I am trying to do, is to redirect users to a webserver inside the LAN the first time they visit certain domains. For example, the first time a user visits "google.com", they will be redirected to 192.168.1.2 (a webserver, where they will be shown a custom webpage), attempts after that will go to google.
Pretty much what I am trying to do, is to provide a captive server like service, showing people a custom webpage the first time they try to access certain websites (but not others). I'm pretty flexable on how this can be done, as long as it works.
Can you guys give me an idea on how to approach this problem? I am looking for (hopefully) a free solutions.