Ironically, the first ever project in my Unix life was Sendmail configuration. It was a project at school in Unix subject. In this project, we were acting like "hosting provider", and required to install, config, secure and maintain dns, mail, file and web services.
At that time, I didnt know Sendmail is that hard
Sounds like I did a good job, havent got any customer's complaint. Oh wait, who is my customer?