Book Image

The Linux DevOps Handbook

By : Damian Wojsław, Grzegorz Adamowicz
3.5 (2)
Book Image

The Linux DevOps Handbook

3.5 (2)
By: Damian Wojsław, Grzegorz Adamowicz

Overview of this book

The Linux DevOps Handbook is a comprehensive resource that caters to both novice and experienced professionals, ensuring a strong foundation in Linux. This book will help you understand how Linux serves as a cornerstone of DevOps, offering the flexibility, stability, and scalability essential for modern software development and operations. You’ll begin by covering Linux distributions, intermediate Linux concepts, and shell scripting to get to grips with automating tasks and streamlining workflows. You’ll then progress to mastering essential day-to-day tools for DevOps tasks. As you learn networking in Linux, you’ll be equipped with connection establishment and troubleshooting skills. You’ll also learn how to use Git for collaboration and efficient code management. The book guides you through Docker concepts for optimizing your DevOps workflows and moves on to advanced DevOps practices, such as monitoring, tracing, and distributed logging. You’ll work with Terraform and GitHub to implement continuous integration (CI)/continuous deployment (CD) pipelines and employ Atlantis for automated software delivery. Additionally, you’ll identify common DevOps pitfalls and strategies to avoid them. By the end of this book, you’ll have built a solid foundation in Linux fundamentals, practical tools, and advanced practices, all contributing to your enhanced Linux skills and successful DevOps implementation.
Table of Contents (20 chapters)
1
Part 1: Linux Basics
6
Part 2: Your Day-to-Day DevOps Tools
12
Part 3: DevOps Cloud Toolkit

Managing users

The user in a Linux system is defined by a set of three files:

  • /etc/passwd: This file contains information about the user – that is, the user’s name, unique numerical ID (UID) in the system, the primary group the user belongs to GID, the path to the home directory, and the shell that is loaded when the user logs in. A typical entry looks like this:
   admin:x:1000:1000:Debian:/home/admin:/bin/bash

Each line describes exactly one user. Fields are separated by a colon. The second field will only contain anything other than x in very exotic cases. Here, x means that the password is stored separately in the /etc/shadow file. The reason is that permissions for the /etc/passwd file have to be a bit more relaxed so that the login process can work. /etc/shadow can only be read by root and root group and written to only by root:

    root@myhome:~# ls -ahl /etc/passwd
    -rw-r--r-- 1 root...