Security should always be considered when installing, deploying, and using any type of computer system. Although a fresh installation of Ubuntu is relatively safe for immediate use on the Internet, it is important to have a balanced understanding of your systems security posture based on how it will be used after deployment.
This chapter provides an overview of security related topics as they pertain to Ubuntu 9.04 Server Edition, and outlines simple measures you may use to protect your server and network from any number of potential security threats.