Book Image

Mastering Linux Administration

By : Alexandru Calcatinge, Julian Balog
Book Image

Mastering Linux Administration

By: Alexandru Calcatinge, Julian Balog

Overview of this book

Linux plays a significant role in modern data center management and provides great versatility in deploying and managing your workloads on-premises and in the cloud. This book covers the important topics you need to know about for your everyday Linux administration tasks. The book starts by helping you understand the Linux command line and how to work with files, packages, and filesystems. You'll then begin administering network services and hardening security, and learn about cloud computing, containers, and orchestration. Once you've learned how to work with the command line, you'll explore the essential Linux commands for managing users, processes, and daemons and discover how to secure your Linux environment using application security frameworks and firewall managers. As you advance through the chapters, you'll work with containers, hypervisors, virtual machines, Ansible, and Kubernetes. You'll also learn how to deploy Linux to the cloud using AWS and Azure. By the end of this Linux book, you'll be well-versed with Linux and have mastered everyday administrative tasks using workflows spanning from on-premises to the cloud. If you also find yourself adopting DevOps practices in the process, we'll consider our mission accomplished.
Table of Contents (20 chapters)
Section 1: Linux Basic Administration
Section 2: Advanced Linux Server Administration
Section 3: Cloud Administration

Managing users

In this context, a user is anyone using a computer or a system resource. In its simplest form, a Linux user or user account is identified by a name and a unique identifier, known as a UID.

From a purely technical point of view, in Linux we have the following types of users:

  • Normal (or regular) users—General-purpose, everyday user accounts, mostly suited for personal use and for common application and file management tasks, with limited access to system-wide resources. A regular user account usually has a login shell and a home directory.
  • System users—These are similar to regular user accounts, except they may lack a login shell or a home directory. System accounts are usually assigned to background application services, mostly for security reasons and to limit the attack surface associated with the related resources—for example, a web server daemon handling public requests should run as a system account, ideally without login or root...