Book Image

Essential Linux Commands

By : Paul Olushile
Book Image

Essential Linux Commands

By: Paul Olushile

Overview of this book

The role of a system administrator is ever-evolving, with the Linux command line at its core. This makes Linux command-line mastery an essential skill to demonstrate your ability to efficiently manage and maintain systems efficiently. Essential Linux Commands addresses a diverse range of topics, including package management, file manipulation, networking strategies, system monitoring, and diagnostic tools. Each command is intricately explained to eliminate any ambiguity, ensuring ease of implementation in real-world scenarios. This book explains how to use SELinux to maintain security, run Linux machines on AWS Cloud, and transfer and download files to remote systems. With the help of practical examples and use cases, you’ll not only gain a thorough understanding of a command’s syntax but also grasp its functional breadth and limitations. The book also explores commands frequently used by system administrators to check network card statistics and firewall rules. Whether you’re a beginner or an experienced administrator, this book is an invaluable resource, filling in the gaps in your skill set and helping you improve your skills and expertise in Linux administration.
Table of Contents (20 chapters)
1
Part 1:Server Installations and Management Commands
5
Part 2:Frequently Used Commands – Part 1
9
Part 3:Frequently Used Commands – Part 2
15
Part 4:Linux Security and the Cloud

Exploring common log files

System administrators check log files for various reasons due to their critical importance in maintaining system health, diagnosing issues, and ensuring security. These logs provide a comprehensive record of system activities, errors, and events, allowing administrators to gain valuable insights into the system’s behavior. For instance, the /var/log/messages log is a goldmine for general system-wide events, which assists in troubleshooting issues that might affect the entire system. This log’s significance lies in its ability to offer a holistic view of the system’s health and performance, aiding administrators in detecting anomalies early on and addressing potential bottlenecks or threats.

Moreover, log files such as /var/log/secure and /var/log/auth.log are pivotal in upholding system security. System administrators continuously monitor these logs to track authentication and authorization activities, helping them identify unauthorized...