What are Ansible handlers and how do they work?

What are Ansible handlers and how do they work?

Ansible handlers are special tasks that run only when notified by other tasks. They are typically used for actions that should only occur once after a change, like restarting a service.

Can you give me an example of how to define a handler?

Sure! You define a handler in your playbook like this:

handlers:
  - name: restart apache
    service:
      name: apache2
      state: restarted

How do I notify a handler from a task?

You can notify a handler by using the notify keyword in your task. For example:

tasks:
  - name: install apache
    apt:
      name: apache2
      state: present
    notify: restart apache

What happens if multiple tasks notify the same handler?

If multiple tasks notify the same handler, the handler will only run once at the end of the playbook execution, ensuring efficiency.