Cyber+Security

How can a linux server and network be setup to practice cyber security?

Cyber Warfare Full Episode http://www.pbs.org/video/2365582515/

https://help.ubuntu.com/lts/serverguide/ http://www.cyberciti.biz/tips/linux-security.html https://plusbryan.com/my-first-5-minutes-on-a-server-or-essential-security-for-linux-servers