Book Image

Linux Essentials - Second Edition

By : Christine Bresnahan, Richard Blum
Book Image

Linux Essentials - Second Edition

By: Christine Bresnahan, Richard Blum

Overview of this book

Linux Essentials, Second Edition provides a solid foundation of knowledge for anyone considering a career in information technology, for anyone new to the Linux operating system, and for anyone who is preparing to sit for the Linux Essentials Exam. Through this engaging resource, you can access key information in a learning-by-doing style. Hands-on tutorials and end-of-chapter exercises and review questions lead you in both learning and applying new information—information that will help you achieve your goals! With the experience provided in this compelling reference, you can sit down for the Linux Essentials Exam with confidence. An open-source operating system, Linux is a UNIX-based platform that is freely updated by developers. The nature of its development means that Linux is a low-cost and secure alternative to other operating systems, and is used in many different IT environments. Passing the Linux Essentials Exam prepares you to apply your knowledge regarding this operating system within the workforce.
Table of Contents (19 chapters)

Protecting Your System from the Bad Guys

Networks provide many useful features for their users. Unfortunately, they also provide many risks. Network security is a complex topic, and we can provide only a few basic tips to help you prevent your system from being compromised. Here are some of the most important things you can do:

Shut Down Unused Servers Linux’s major security vulnerabilities aren’t in worms and viruses, as they are with Windows; in Linux, the risks center on outsiders breaking into your computer by abusing server programs that you run. Therefore, it’s important that you don’t run servers unnecessarily. Some distributions automatically install and run servers, such as the Secure Shell (SSH), the Apache web server, or a mail server such as Sendmail or Postfix. The most thorough way to remove a server is to uninstall it by using your package system (described in Chapter 9, “Exploring Processes and Process Data”)—but you must...