Ansible

The Practical Guide for Administrators and DevOps Teams
1. Auflage 2025
ISBN: 978-1-4932-2702-0
Verlag: Rheinwerk Verlag GmbH

Buch, Englisch, 474 Seiten, Format (B × H): 178 mm x 254 mm

If you want to keep your servers in order, Ansible is the tool of choice! In this practical guide, you’ll learn how to use Ansible to automate server configuration, software deployment, and more. Start by installing Ansible and setting up your initial inventory management process. Then, follow step-by-step instructions for system orchestration, from the basics of playbooks and tasks to using Ansible with Docker. With expert tips and best practices for testing, debugging, and more, this is your all-in-one guide to automating with Ansible!

Highlights include:
1) Basic setup
2) Inventory management
3) Ad-hoc commands and patterns
4) YAML
5) Playbooks, tasks, and plays
6) Modularization
7) Roles
8) Includes
9) Module library
10) Web interfaces
11) Docker
12) Custom collections and modules

Autoren/Hrsg.

Miesen, Axel

Fachgebiete

• Mathematik | Informatik EDV | Informatik Betriebssysteme Virtuelle Maschinen, Virtualisierung

Inhaltsverzeichnis

. Preface. 21

. About This Book. 23

. Formatting. 23

. Ansible Versions. 25

. Platforms and Linux Distributions. 25

1. Introduction and Installation. 27

1.1. What Is Ansible?. 27

1.2. What Is Ansible Not?. 29

1.3. History and Versions. 30

1.4. Setup/Lab Environment. 31

1.5. Ansible Installation on the Control Host. 36

1.6. Installation via PIP (plus virtualenv). 38

1.7. Authentication and Authorization on Target Hosts. 39

1.8. Setting Up SSH Public Key Authentication. 41

1.9. An Ad Hoc Test without Any Configuration. 42

1.10. Another Note on Migrating from Older Versions. 43

2. Basic Setup and Initial Inventory Management. 45

2.1. Setting Up the Directory Structure. 45

2.2. Basic Configuration (ansible.cfg). 46

2.3. Creating and Managing a Static Inventory. 48

2.4. Configuration Settings versus Parameters versus …?. 50

2.5. Inventory Aliases and Namespaces. 51

2.6. Beyond Ping. 53

2.7. A Somewhat More Complex Example. 55

2.8. Alternative or Multiple Inventories. 56

3. Ad Hoc Commands and Patterns. 59

3.1. Ad Hoc Commands. 59

3.2. Use Cases Beyond “command” and “shell”. 61

3.3. Idempotency. 61

3.4. Internal Workings. 63

3.5. The Ansible Console. 66

3.6. Patterns for Addressing Hosts. 67

4. YAML: The Configuration and Serialization Language. 69

4.1. Syntax and Structure. 69

4.2. Editing YAML Files. 70

4.3. Syntactic Checks. 72

4.4. Lists and Maps. 73

4.5. Nested Structures. 73

4.6. Text Passages and Block Expressions. 75

4.7. Nothingness in YAML. 76

4.8. Anchors and References. 77

5. Playbooks and Tasks: The Basics. 79

5.1. Hello Ansible: The Very First Playbook. 79

5.2. Formulation of Tasks. 83

5.3. Ending Plays. 85

5.4. The Problematic Colon. 85

5.5. Error Handling and Retrying Files. 86

5.6. Tags. 88

5.7. The “ansible-playbook” Command. 90

5.8. An Example of an Apache Installation. 91

5.9. Handler: Executing Tasks Only on Changes. 95

6. Playbooks and Tasks: Advanced Methods. 103

6.1. Variables. 103

6.2. Registered Variables. 112

6.3. Facts and Implicit Variables. 115

6.4. Conditional Execution with “when”. 121

6.5. Handling System Differences: What’s the Deal Now?. 122

6.6. Jinja and Templates. 131

6.7. Variable Tests. 141

6.8. Lookup Plug-ins. 143

6.9. Loops. 145

6.10. Error Handling with “failed_when” and “ignore_errors”. 158

6.11. Blocks. 159

6.12. Timeouts and Asynchronous Execution. 161

6.13. Local Tasks. 163

6.14. Environment Variables. 166

7. Using Modules and Collections. 169

7.1. Collections. 169

7.2. Module. 173

7.3. Modules for Command Execution. 174

7.4. Modules for Package Management. 175

7.5. Modules for Managing Files and File Contents. 177

7.6. Modules for Other Typical Administrative Tasks. 182

7.7. Modules for Interacting with Network Services. 185

7.8. Special Modules (Control Flow Management, Etc.). 186

8. Modularization with Roles and Includes. 191

8.1. Creating and Using Roles. 191

8.2. The Online Ansible Galaxy Repository. 198

8.3. Using Imports and Includes. 198

8.4. Apache Once Again. 202

8.5. Documentation (and Conventions). 206

8.6. Reusing Roles. 209

9. Web Interfaces: AWX and More. 213

9.1. Installation of Python Packages on Current Debian and Ubuntu Systems. 213

9.2. Ansible Configuration Management Database (“ansible-cmdb”). 214

9.3. Preparations for Operating More Demanding Applications. 216

9.4. The Gitea Git Server. 219

9.5. AWX. 223

9.6. ARA. 229

9.7. Other Applications Not Considered in Detail Here. 230

9.8. Terminating or Deleting Applications That Are No Longer Needed. 233

10. Additional Tools and Techniques. 235

10.1. Ansible Vault. 235

10.2. Debugging and Troubleshooting. 244

10.3. Accelerating Playbooks with Pipelining. 257

10.4. The Talking Cow. 258

10.5. Ansible in Pull Mode. 259

11. Ansible and Docker. 265

11.1. Installing Docker. 265

11.2. Docker Modules. 267

11.3. An Example Application. 274

11.4. Ansible and Docker Compose. 278

11.5. The “docker” Connection Plug-in. 282

11.6. Creating Images. 283

12. Inventory Management: Advanced Methods. 289

12.1. The “ansible-inventory” Command. 289

12.2. Nested Groups. 290

12.3. Static Inventories in YAML format. 291

12.4. Creating on-the-Fly Inventories with “add_host”. 293

12.5. Dynamic Groups with “group_by”. 295

12.6. Dynamic and External Inventories. 298

13. Ansible and the Cloud. 303

13.1. Version Issues and virtualenv. 304

13.2. Where to Store Keys, Tokens, Secrets, Etc. 304

13.3. Hetzner Cloud. 305

13.4. Amazon Web Services Elastic Compute Cloud. 311

13.5. Proxmox Virtual Environment. 318

14. Ansible as an Orchestration Tool. 325

14.1. Many Target Hosts for Testing. 325

14.2. Altering the Sequence of Execution. 326

14.3. Delegation. 335

15. Ansible and Windows. 339

15.1. A Control Host Based on Windows. 339

15.2. Windows Targets and Windows Remote Management. 343

15.3. Preparations on the Control Host. 343

15.4. Prerequisites on the Windows Side and Windows Remote Management Setup. 344

15.5. Windows Remote Management Troubleshooting. 345

15.6. Setup with an Active Directory and Kerberos. 346

15.7. Windows Modules. 348

16. Callback Plug-ins. 351

16.1. Stdout Callback Plug-ins. 351

16.2. Aggregate and Notification Callback Plug-ins. 353

17. Creating Your Own Collections and Modules. 355

17.1. Namespaces, Names, and Setting Up a Collection Project. 355

17.2. Playbooks in Collections. 357

17.3. Roles in Collections. 358

17.4. Modules in Collections. 359

17.5. Plug-ins in Collections. 371

17.6. Deploying and Installing Collections. 373

18. Developing and Testing with Molecule. 377

18.1. Preparations and Setup. 377

18.2. Getting Started. 379

18.3. Develop. 380

18.4. Testing with the Ansible Verifier. 383

18.5. Testing with the Testinfra Verifier. 385

18.6. The Complete Test Cycle. 386

18.7. Outlook and Conclusion. 387

19. Recipes, How-Tos, and Best Practices. 389

19.1. New Projects. 389

19.2. Administration. 391

19.3. Jinja Magic. 401

19.4. Tasks and Control Flow. 408

19.5. Miscellaneous. 415

20. What Could Be Better, and What Is Still Missing?. 421

20.1. Tracking Long-Running Tasks. 421

20.2. Finishing the Processing of a Role. 422

20.3. Loops over Blocks. 424

20.4. Locking with Concurrent Playbook Calls. 425

20.5. Conclusion. 426

. Appendices. 427

A. Project-Specific Environment Variables with “direnv”. 429

B. The “pass” Password Manager. 433

C. Secure Shell. 437

D. Regular Expressions. 455

E. “vim” and “nano” Tips and Tricks. 463

. The Author. 467

. Index. 469

Über Autor(innen)

Miesen, Axel
Axel Miesen is an Ansible coach. His interest in Linux systems began with his studies at the University of Kaiserslautern, where he studied mathematics and computer science. After graduating in 1998, he began working as a consultant and trainer and has passed on his Linux knowledge and experience to numerous professionals.