answer:I dont know of any tutorials online. But I do highly suggest keeping a close copy of this “cheat sheet”
http://fosswire.com/post/2007/08/unixlinux-command-cheat-sheet/ I would say the most important thing to really understand is how to use apt-get to add/remove packages. Also that how to start and stop services. Deamons are running ”/etc/init.d/” so to restart mysql would be something, “sudo /etc/init.d/mysql restart”. Most conf files are in ”/etc” folder in their own directories. For example Apaches conf file is under ”/etc/apache/httpd.conf”. And don’t forget your logs under ”/var/log/”. Other then that, mess around and get a good feel for running the server. the “man” command is probably going to be your best friend. Never use the root user, you should use sudo to execute super user commands. As far as ports though, only open up ones you need, for example 80 if your running a web server, 110 for POP3, and 25 for STMP, 21 for FTP, 22 for SSH (I would suggest switching to something else to stop attacks like port 2995, or 512. People scan for that port to be open and try to ssh in to your box), and 3306 for MySQL. hope that helps