I have a ASP.NET application (C#), just a form for people to fill out and submit on the Internet. However, I need this application to write a file (just using IO) to a location on my LAN. This is a problem because of the DMZ.
From what I understand, the purpose of the DMZ is that no connections from the big scary Internet is allowed through to the LAN.
Internet —> LAN: blocked
LAN —> Internet: allowed
Internet —> DMZ: Only certain ports
LAN —> DMZ: allowed
DMZ —> LAN: blocked
So what can I do?
If you have NOTHING available from the DMZ –> LAN then about the only thing you can do is write the file locally and have a service in the LAN that polls for the files, copying them in when it finds them. The polling routine could be as simple as a batch file running on a scheduled task that just blindly copies anything in a folder on the web server in the DMZ to a location internally.