RE: Protecting an Exchange server?

["Sanjay K. Patel" <sanjay.patel () rexwire com>]

 What you trying to do is put a relay server in the DMZ. All external e-mail
will come from the internet to this relay server which will than forward it
to the Exchange server located in your LAN. Cheapest way to do this is to
setup a linux box running sendmail in your DMZ. This box will receive all
mail and than forward it to your Exchange box. One of the benefits of this
could be you can do virus and spam filtering on this box thus taking the
load of Exchange.

This is very simple to do.

-SKP

-----Original Message-----
From: Mark G. Spencer [mailto:mspencer () evidentdata com] 
Sent: Thursday, May 13, 2004 1:52 PM
To: security-basics () securityfocus com
Subject: Protecting an Exchange server?

Hello,

I'm wondering if there is any way to locate an Exchange server on my
internal network and place some kind of email appliance on our DMZ to
actually send and receive email to the world and to the Exchange server on
my internal network?

Basically, I don't want my Exchange server to be accessible to the world in
any way.

So ..

Internet -> My Email Appliance -> Firewall -> Exchange Server

I envision setting up a dedicated route in the firewall between the email
appliance out on the Internet and my Exchange server behind the firewall on
my local network?

Are there any email appliances that can work with Exchange in this way?
It's my (limited) understanding that Exchange server can't "pop" to another
email server to pull each Exchange users email, so I'm not sure exactly how
or if my plan could be put into action.

Thanks,

Mark





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