Where can I get a list of Ansible pre-defined variables?

Question

I see that Ansible provide some pre-defined variables that we can use in playbooks and template files. For example, the host ip address is ansible_eth0.ipv4.address. Googlei

Answer 1

I use this simple playbook:

---
# vars.yml
#
# Shows the value of all variables/facts.
#
# Example:
#
#   ansible-playbook vars.yml -e 'hosts=localhost'
#
- hosts: localhost
  tasks:
    - fail: "You must specify a value for `hosts` variable - e.g.: ansible-playbook vars.yml -e 'hosts=localhost'"
      when: hosts is not defined

- hosts: "{{ hosts }}"
  tasks:
    - debug: var=vars
    - debug: var=hostvars[inventory_hostname]