While debugging an Ansible playbook, I tweeted about variable precedence:
https://twitter.com/andyhky/status/734859666337861633
Through that tweet I learned how to spell mnemonic AND I got a recommendation to buy Mastering Ansible. This blog post is a quick review of Mastering Ansible.
Overall, I enjoyed the book’s format more than anything else. The flow of objective/code/screenshot really made the concepts gel (using herp/derp in examples is a close second!). I’m an advanced Ansible user (over 3 years), and this book still showed me new parts of Ansible. The book had very useful suggestions for playbook optimization and simplification. Mastering Ansible also provided some nifty tips and tricks like Jinja Macros, ansible-vault with a script, and merging hashes that I didn’t know were possible.
Of course the book answered my variable precedence question - another thing it did was provide some clarity around using variables with includes which was what I really needed.
If you’re just getting your feet wet with Ansible or you’ve been using it for years, Mastering Ansible is worth picking up.