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

Working with daemons

As noted in the introductory sections, daemons are a special breed of background process. Consequently, the vast majority of methods and techniques for working with processes also apply to daemons. However, there are specific commands that strictly operate on daemons when it comes to managing (or controlling) the lifetime of the related processes.

As noted in the Daemons section, daemon processes are controlled by shell scripts, usually stored in the /etc/init.d/ or /lib/systemd/ system directories, depending on the Linux platform. On legacy Linux systems (for example, CentOS/RHEL 6) and Ubuntu (even in the latest distros), the daemon script files are stored in /etc/init.d/. On CentOS/RHEL 7 and newer platforms, they are typically stored in /lib/systemd/.

The location of the daemon files and the daemon command-line utilities largely depends on the init initialization system and service manager. In The init process section, we briefly mentioned a variety of...