Book Image

Practical Linux Security Cookbook

By : Michael A Lindner, Tajinder Kalsi
Book Image

Practical Linux Security Cookbook

By: Michael A Lindner, Tajinder Kalsi

Overview of this book

With the growing popularity of Linux, more and more administrators have started moving to the system to create networks or servers for any task. This also makes Linux the first choice for any attacker now. Due to the lack of information about security-related attacks, administrators now face issues in dealing with these attackers as quickly as possible. Learning about the different types of Linux security will help create a more secure Linux system. Whether you are new to Linux administration or experienced, this book will provide you with the skills to make systems more secure. With lots of step-by-step recipes, the book starts by introducing you to various threats to Linux systems. You then get to walk through customizing the Linux kernel and securing local files. Next you will move on to manage user authentication locally and remotely and also mitigate network attacks. Finally, you will learn to patch bash vulnerability and monitor system logs for security. With several screenshots in each example, the book will supply a great learning experience and help you create more secure Linux systems.
Table of Contents (17 chapters)
Practical Linux Security Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Using system tools – strace


When running any command or program on our Linux machine, you might wonder what the background working of it is. For this, we have a very useful tool in Linux called strace.

This a command-line tool that can be also used as a diagnostic or debugging tool. strace monitors the interaction between processes and the Linux kernel and is helpful when we want to debug the execution of any program.

Getting ready

This tool is available for all Linux-based systems by default. Hence, nothing else needs to be configured to start using strace.

How to do it…

Let's see how strace can be used in various ways to trace the execution of any program from start to end.

  1. To trace the execution of any executable command in Linux, simply run the strace command followed by the executable command. If we use strace for the ls command, we get this output:

  2. In the preceding screenshot, the output displayed has been truncated. If we check the last few lines of the output, we see some write system calls...