How to redirect a specific TCP port to a different IP?

[Mike Haney]

I'm hoping someone out there will be able to lend a hand in figuring
this out as I am stumped. I am replacing an aged linux box that was
used for wireless network gateway authentication with a Windows 2000
Server box with a RAS/VPN setup, and everything in that respect is
working quite fine.

My problem is that on the old linux box I could redirect all TCP port
80 traffic from the wireless clients to the local linux box webserver
so they could use the local login webpage before proceeding out to the
internet (ie. someone opens a browser and goes to www.yahoo.com before
logging in, the linux box would drag them back to the login page
first). I know how to accomplish this using iptables in linux but
can't seem to find a way to do this in Windows 2000?

I was thinking that even a fake DNS server would be sufficient where
the fake DNS server would provide local connections with the IP
address of the Windows 2000 server for every DNS request regardless of
the name... When the clients connect via the VPN a new DNS server
(that would properly hand out resolution information) would be passed
to the VPN client connection...

Any ideas?

Thanks in advance!
Mike

 

[Thor Kottelin]

My problem is that on the old linux box I could redirect all TCP port
80 traffic from the wireless clients to the local linux box webserver
so they could use the local login webpage before proceeding out to the
internet (ie. someone opens a browser and goes to www.yahoo.com before
logging in, the linux box would drag them back to the login page
first). I know how to accomplish this using iptables in linux but
can't seem to find a way to do this in Windows 2000?

Install a proxy server, deny direct outgoing access to port 80, and set up
user authentication on the proxy? If you're familiar with Apache for Linux,
you're almost familiar with Apache for Windows as well.

Follow-ups narrowed.

Thor

 

[Markus E. Kippler]

Sounds like this might work for you: www.dnsredirector.com