FreeBSD as buffer to exchange server

[jimthecanadian]

I have an exchange server inside my firewall and a FreeBSD box in the dmz that accepts mail for all users and forwards it to the exchange server. The BSD box has sendmail and Spam Assassin.

This setup is great for incoming mail but it does not work for local users sending mail from outside the company. I would like to implement some of the security features in sendmail for all users, including the exchange users but the problem is I cannot figure out how to get the users authenticated against the NT domain.

I have tried using LDAP but the exchange 5.5 version of LDAP seems to be non standard. Anyone have an suggestions?

 

[AHinMaine]

Right in the ports collection.

http://www.freshports.org/security/pam_smb/

--
Andy

http://www.nachoz.com

"Historically speaking, the presence of wheels in Unix has never precluded their reinvention."
Larry Wall

 

[ikester]

Hi,

As I am somewhat of an email newbie, can you tell me how you setup your BSD box to forward the email to exchange?
Its probably easy, but I am wondering if you had to set the exchange server to pickup the mail? Also how did you do your DNS MX records? Here is the problem I am trying to solve: I want a second email server for example.com (at a seperate location) to receive email automatically for our front line exchange server when it is offline. Then when it is back up, I would like the email gathered by the higher MX record to automatically forward what it received to the exchange server OR have the exchange server pick it up?
Your help iwll be immensely appreciated!

 

[jimthecanadian]

The way I do this is: On my firewall I block all access to the exchange server on port 25 and open access on port 25 to the BSD box. I then make an MX record in DNS pointing to the BSD box. (I leave port 110 open on the exchange box so the users can pick up their mail directly form the server).

Now on your BSD box all you have to do is set up sendmail to act as a smarthost and accept mail and forward it to the exchange server. I also had someone set up Spam assassin on the BSD box as well. I highly recomend it.

There is something else you can do here. if you like you can set up the BSD box as the primary MX server and exchange as a secondary. That way if something happens to the BSD box the mail will go to the exchange box. I personaly did not do this becuase SPAMers will use it to bypass your spam filter on the BSD box.

 

[ikester]

Thanks Jim~!

I guess the part I am the most confused on is "set up sendmail to act as a smarthost and accept mail and forward it to the exchange server" This is what I don't get. right now I just took a break from "Reading The Fine Manual" to do email and saw this post. Thanks again~!

Ikester