Ansible Training Notes
Ansible allows much more control over the execution of the playbook by running the tasks in parallel on all hosts. By default, Ansible only fork up to five times, so it will run a particular task on five different machines at once.
In order to complete some configuration tasks, it may be necessary for actions to be taken on a different server than the one being configured. Some examples of this might include an action that requires waiting for the server to be restarted, adding a server to a load balancer or a monitoring server, or making changes to the DHCP or DNS database needed for the server being configured.