Re: Protecting an Exchange server?

[Niek <niek () packetstorm nu>]

Mark G. Spencer wrote:

> 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

Mark,

setup a *nix/*bsd/ect machine with a MTA (qmail/postfix/exim/ect) which does virus/spam
checking ect. This machine resides on a wan ip (the ip of the mx of your domain).
Configure the MTA that it accepts the mail, then forwards it to the exchange server.

On the exchange server, configure it to use the *nix/*bsd/ect machine as smarthost.
There are lots of howtos for qmail/postfix/exim configurations like what i am describing.
Google will find them for you.

Good luck,
Niek


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