Setting Up A Mail Server On Linux
I have found that most people have found my blog by searching for how to set-up a mail server on Linux so I throught I should elaborate on how I set mine up.
The tutorial
I first followed the guide supplied by Slicehost but found that it is not complete. I then discovered and followed an article from unix-tutorials.com which I recommend.
This article is easy to follow and gives you a great understanding of what each step does.
It shows you how to set-up a mail server for multiple domains and setting quotas for each address. When complete you can access your mail over TLS or SSL so that it is encrypted. The one downside I found though is that you can only apply one certificate to all domains.
Here are some important pieces in more detail:
Creating Certificates
One thing left out of both tutorials was how to create your own Courier certificates for receiving email. Without creating your own, you are left with a warning that the certificate is for localhost every time you connect to the server. I found a tutorial from another blog blog.edseek.com that explains how to create your own self signed certificate. You will still get a warning but your mail client should allow you to accept that self signed certificate permanenetly.
Setting Quota
The tutorial from unix-tutorials also shows how to set quotas for email address. Along with this you will receive (via a cron job) an email advising of any mail accounts approaching their quota.
Slow performance
One issue I did have in all this was the slow performance this caused on my slice. With all the Spam detection and Anti virus running in the background my websites were crawling to a halt. This was because my slice had only 256MB of RAM. It would be fine if I upgraded but at this time I can do without the extra filtering on the mail. For now I have had to disable the spam filter and and anti-virus until it comes the time to upgrade the slice.
Conclusion
In all this is a valuable experience for anyone who wishes to learn more about Linux and wants more control of there server and services.