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by todd r

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We are currently setting up a test network with a firewall, DMZ, and email. After many hours of research we have decided to leave the email server inside the internal network instead of placing the server in the DMZ due to the vast number of ports that must be left open to use Exchange in the DMZ (MS Knowledge Base Article 278339). We have decided to place a machine in the DMZ to act strictly as a SMTP forwarder and forward traffic strictly for port 25 to Exchange in the internal network. Every piece of information I have been able to find regarding fowarders points to using a Linux/Unix box which we would rather not use at this time due to support reasons. Does anyone know of a Windows-based fowarder that would fit out needs? Any additional tips would be appreciated.

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by dukebytes

I may not be thinkning correctly - but can't you set up a regular sever as a messaging center of some sort? I'm sure it would hop mail for you to the inside - If they still have it for Win2K or whatever you are using. There might be a restriction on the number of messages that you can hop - not sure??

You might want to look into Imail. Cheap - works great - and you can get a version of it with virus checking software built right into the smtp service.

A FreeBSD/Linux box with a mail hopper on it would be easier than you think tho - and it would be CHEAP :)

Reguardless of what you do - make sure that you have smtp gateway virus protection software on your inside server.

Good luck,
Duke

by lordinfidel

You can just use NT4 IIS or 2K IIS with smtp enabled to relay and forward mail back and forth.

Point your MX record to the server in the DMZ. Set up IIS SMTP to forward the domains to your exch server.

In IIS in the smtp service, add a new remote domain, type in the domain name like domain.com.
Use the forward to smart host option and specify the exchange server fqdn.

To relay, right click on the smtp server, properties, under access, you will see relay restirctions. Make sure you lock it down so that only the exch server can relay thru it.

The in your exch admin (assuming 5.5) in the IMS, deliver all outbound mail to the relay server.

by woody

You can install a base Cygwin (UNIX enviroment for Win32) distribution on your favorite version of Windows and select the Exim package under the Mail catagory. Exim is a robust SMTP package that also can be configured to forward email for a domain or domains.

Cygwin itself is a port of a large number of traditionally UNIX utilities for the Win32 platform and a great way to get a Unix type enviroment on Windows or use UNIX utilities without having to learn how to administer a UNIX or Linux system.

While I would lean towards implementing Linux for the functionality you are describing, I can certainly understand the support issues involved for a potentially understaffed IT department having to learn and at the same time implement a completely new platform.

Another advantage of Cygwin is you get to use the utilities and if you do choose to implement a UNIX or Linux system later, application migragtion is that much easier.

There is a wealth of help available on the web for Cygwin in similar fashion to traditional Linux peer support. Exim itself has loads of web-based help and there is a book published by O'Reilly, "Exim The Mail Tranfer Agent" by Philip Hazel.

Cygwin can be found at www.cygwin.com. The setup of Cygwin will allow you to install Exim at that time. You can also rerun the Cygwin setup at any time to update, uninstall, or install additional packages.

I would also suyggest you pick up an editor that understands UNIX carrige returns such as PFE (Programmer's File Editor - http://www.lancs.ac.uk/people/cpaap/pfe/). Most of the Cygwin documention will appear rather poorly formatted in Windows Notepad (lots of squares where line breaks should be).

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