As your playbooks become increasingly complex, it becomes more and more important that you have robust ways to debug any issues that might arise. For example, is there a way you can check the contents of a given variable (or variables) during execution without the need to insert debug statements throughout your playbook? Similarly, we have so far seen that Ansible will ensure that a particular task runs to completion on all inventory hosts that it applies to before moving on to the next task—is there a way to vary this?

When you are getting started with Ansible, the execution strategy that you see by default (and we have seen this so far in every playbook we have executed, even though we have not mentioned it by name) is known as linear. This does exactly what it describes—each task is executed in turn on all applicable hosts...