Good morning everyone!!

I have been charged with setting up an email server for my company. I last did this in (gasp) 2000 with qmail on RedHat (I think 7.1 at the time).

Anyways, I have sort of settled on CentOS as the OS, and Scalix as the email system.

To be efficient, I want to set it up so my users connect to it over the LAN when they're at work. Of course, it will need a NIC to the DMZ of my PIX firewall so the outside world can send us email. So my question is, how do I set it up so it has that outside interface, but reduce the chances that someone comes in on that outside NIC and gets access to my inside network??

And if you have any recommendations on Email servers, feel free to tell me that too!!! I have my reservations about Scalix, though the web interface is very snazzy.

Thanks.

You can minimize your exposure by only allowing traffic on port 25 to the mail server. Also placing it in the DMZ would help.

I'm currently using sendmail for an MTA and dovecot for POP/IMAP server. The front end we're using is Horde:

http://www.horde.org/

Has all the functionality of any groupware suite, but it integrates with your existing mail servers which is nice.

Thats my 2cents anyway.

There is a super easy setup guide for qmail+squirrelmail+spamassassin+clamav at http://qmailrocks.org . It is so simple a *nix newbie can get through it. In your situation, behind a hardware firewall, it should be secure enough. As stated above, only allow access from the WAN to port 25, and add 110 for pop3 or 143 for imap if you want people to be able to access those services outside the office. There are GUI webpages for adding/removing domains, and you can set up forwarding rules, vacation messages and most things through one of the local sites, and the other allows you to see info like when an individual account was last accessed, and what its current password is. Obviously those should be very heavily protected from the outside world, probably not even available outside the office.

Peace,
JimBass

how large a system are you looking to impliment? 10 users? 1000? 100000?

I use cyrus for a small setup, but it is nicely scalable to much larger systems.