Practical Ansible: Configuration Management from Start to Finish

276 Pages·2021·3.015 MB·English

by  Vincent Sesto

Practical
Ansible
Configuration Management from
Start to Finish
—
Vincent Sesto
Practical Ansible
Configuration Management
from Start to Finish
Vincent Sesto
Practical Ansible: Configuration Management from Start to Finish
Vincent Sesto
Auckland, New Zealand
ISBN-13 (pbk): 978-1-4842-6484-3 ISBN-13 (electronic): 978-1-4842-6485-0
https://doi.org/10.1007/978-1-4842-6485-0
Copyright © 2021 by Vincent Sesto
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Table of Contents
About the Author ���������������������������������������������������������������������������������ix
About the Technical Reviewer �������������������������������������������������������������xi
Preface ����������������������������������������������������������������������������������������������xiii
Introduction ��������������������������������������������������������������������������������������xvii
Chapter 1: Configuration Management with Ansible ����������������������������1
Getting Started with Configuration Management2
Why Ansible? 3
Getting Started with Ansible 6
Installing Ansible 7
Ansible Support for SSH 9
Finally, Our First Ansible Command 12
Basic Ansible Playbooks 13
Ansible Configuration and Inventory Files 16
Running Ansible Modules 20
Ping 20
Setup 21
Git 22
Shell23
Apt (or Yum) 24
Service 25
get_url 26
v
Table of ConTenTs
file27
user 28
find 29
Running Ansible on Different Servers 30
Different Versions of Ansible 32
Ansible Projects 32
Basic LAMP Stack 32
Splunk Server Environment 33
Summary34
Chapter 2: Ansible Playbooks �������������������������������������������������������������35
Ansible and YAML Syntax 36
Command-Line Modules to Ansible Playbooks 39
Ansible Playbook Verbose Output 46
Ansible Syntax in Finer Detail 47
Hosts and Remote Users 47
Tasks 49
Notify 50
Adding More Playbook Functionality with Variables and Loops 51
Plugging In Our LAMP Stack 58
Organizing Larger Playbooks with Include and Import 66
Summary69
Chapter 3: Extending Playbooks with Roles and Templates ���������������71
Ansible Roles 72
Creating the Web Server Role 73
Creating the Database Server Role 80
Ansible Command-Line Variables and Options 84
vi
Table of ConTenTs
Expanding Our LAMP with Django 85
Conditional Tasks in Ansible 94
Using Tags to Run Specific Tasks 97
Summary101
Chapter 4: Custom Ansible Modules, Vaults, and Galaxies ���������������103
Keeping Secret with Ansible Vault 104
Ansible Galaxy 110
Searching and Working with Ansible Galaxy Roles 111
Downloading and Installing Multiple Roles from Galaxy 120
Moving Further with Ansible Galaxy 123
Contributing to Ansible Galaxy 127
Building Your Own Ansible Modules 135
Summary142
Chapter 5: Working with Ansible in the Amazon Cloud ��������������������143
So Why Amazon Web Services 144
AWS Is Not Free 145
AWS Pricing 145
Gaining Access to AWS145
Using Environment Variables to Access AWS 153
Ansible AWS Modules to Implement Our New Project 153
Our New Splunk Implementation Project 154
Creating Our AWS Instance 159
Deploying Splunk with User Data 170
Failures on Amazon Web Services 176
Summary178
vii
Table of ConTenTs
Chapter 6: Ansible Templates and CloudFormation Scripts �������������179
One Final Word on AWS Costs 180
Ansible Templates in AWS Instances 181
Pulling Code with Ansible189
Ansible Pull GitHub Repository Deployment Explained 195
Build AWS Images for Quicker Deployments 196
Using CloudFormation with Ansible 203
Summary213
Chapter 7: Ansible Tests and Variables ��������������������������������������������215
AWS Modules Run Differently 216
Using the Debug Module with Registered Variables 218
Ansible Facts 224
Testing Ansible As You Develop 228
Ansible Start At Option 229
Ansible Step 230
Ansible Lint 231
List Ansible Tasks 239
Ansible Check Mode 240
Ansible Playbook Syntax Check 243
Ansible Testing with Molecule244
Summary257
Index �������������������������������������������������������������������������������������������������259
viii
About the Author
Vincent Sesto is a DevOps engineer, endurance athlete, and author.
As a DevOps engineer, he specializes working with Linux and open
source applications. He is particularly interested in helping people get
more from the tools they have and is currently developing his skills in
DevOps, continuous integration, security, Splunk (UI and Reporting),
and Python development.
ix
About the Technical Reviewer
Lamodar Ray is an IT professional in the
United States. He is a database specialist
with focused expertise in Amazon Cloud
services and Oracle Cloud Infrastructure.
He has worked in delivering database and
infrastructure solutions in diverse industry
and business domains including workforce
management, finance, procurement ,
manufacturing , sales, and compensation.
He is also a Certified Oracle Cloud Architect
Professional and Amazon AWS Architect
Associate.
xi