Email Server Setup

I work as a Systems Administrator for a school. We have our own Mail Server that runs on Mdaemon. I have my network running on local IP (192.168.x.x). I have a cisco router that has a real ip and a local ip. My mail server is running on local IP. I have defined NAT (in fact PAT) rules to re-direct trafffic from router to mail server and vice versa. The problem is that some of the domains (like AOL) traces the source of the email and get my local IP as source IP thus deny or reject the email generated from our mail server.

I want to switch my mail server to a real IP. What is the best way to accomplish this? I do have available real IPs. My concerns are:

1. Security
2. Functionality
3. Simplicity of the solution

Will I have to make my mail server a multihome system (with two NICs, one facing the LAN and other facing the WAN)?

I will really appreciate your help. Thanks.
ikhanrAsked:
Who is Participating?

Improve company productivity with a Business Account.Sign Up

x
 
ridConnect With a Mentor Commented:
Your ISP. They give you your IP and should have the authoritative DNS entry for this IP, no? Make sure there is a proper MX record for your domain name pointing to your IP and that all other entrieas are OK. Of course, the www.domain.com should resolve to whatever IP your web hosting company uses. A lot of useful info can be had by trying out your domain name or IP on the www.dnsstuff.com website.
/RID
0
 
SembeeCommented:
I doubt whether it is the local IP address that AOL is having a problem with.
If it was, then they would have a problem with 90%, if not more of the email servers on the internet.

Have you looked at the AOL postmaster web site? http://postmaster.aol.com/
That will have lots of information on why emails may be blocked.

Put your domain in to dnsreport.com and see if it flags any errors.
The most common which cause problems with AOL are SMTP banner not matching the DNS, reverse DNS not present and forward DNS incorrect or not present.

Simon.
0
 
ridCommented:
Agree with the above. Even many large organisations use the NAT/PAT solution without problems. I suppose you could have your mail server in the "DMZ" (assuming your router has such an option), but I'd investigate the problem more in detail before changing the setup if I were in your situation.
/RID
0
Free Tool: IP Lookup

Get more info about an IP address or domain name, such as organization, abuse contacts and geolocation.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

 
ikhanrAuthor Commented:
Thanks guys. I will look into more details of the problem. Thanks for the guidline.
0
 
R-YaninCommented:
Look into adding an RVP DNS record to your public DNS records yahoo AOL Microsoft and some others are very stringent on their reverse DNS lookups and are a common grievance with e-mail sent to them. AOL is the most strictly enforced reverse lookup organization I am familiar with.
0
 
ikhanrAuthor Commented:
I have a weird kind of setup (actually I have inherited it from our school's previous systems administrator). We have a website that is hosted by a hosting company. I have some of the dns records defined on their dns server. Then we have our ISP taking care of our Internet access.

Where do you guys think I should start to look for a solution first?

0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.