== Installing ansible ==

{{{#!highlight sh numbers=off
# Official PPA for Ubuntu
sudo apt-add-repository -y ppa:ansible/ansible
sudo apt-get update
sudo apt-get install -y ansible
}}}

== Playbooks meant to only be run locally ==

{{{#!highlight yaml
- hosts: local
  connection: local
  become: yes
  become_user: root
  tasks:
   - name: Install Nginx
     apt:
       name: nginx
       state: installed
       update_cache: true
}}}

or specify hosts: all:

{{{#!highlight yaml
- hosts: all
  become: yes
  become_user: root
  tasks:
   - name: Install Nginx
     apt:
       name: nginx
       state: installed
       update_cache: true
}}}

and then invoke ansible with:

{{{#!highlight sh numbers=off
ansible-playbook -i 'localhost,' -c local Playbook.ansible.yml
}}}

== Disable SSH host key checking ==

Export `ANSIBLE_HOST_KEY_CHECKING` before running ansible:

{{{#!highlight sh numbers=off
ANSIBLE_HOST_KEY_CHECKING=False ansible -i inventory.yml all -m ping
}}}

or into ansible.cfg put:

{{{
[defaults]
host_key_checking = False
}}}

== Async/parallelizing tasks ==

See http://toroid.org/ansible-parallel-dispatch and https://docs.ansible.com/ansible/latest/user_guide/playbooks_async.html, and https://blog.crisp.se/2018/01/27/maxwenzin/how-to-run-ansible-tasks-in-parallel, needs more research.

== Tips & tricks ==

{{{#!highlight sh
# Start at a specific named task, e.g. the one called "install packages"
ansible-playbook playbook.yml --start-at="install packages"
}}}

== Good articles ==

 * [[https://serversforhackers.com/c/an-ansible2-tutorial|An Ansible2 Tutorial]]
 * [[https://linuxctl.com/2017/01/ansible---interacting-with-external-rest-api/|Ansible - Interacting with external REST APIs]]

== Filters ==

 * [[https://docs.ansible.com/ansible/latest/user_guide/playbooks_filters.html|Filters in Ansible's documentation]]
 * [[http://jinja.pocoo.org/docs/latest/templates/#builtin-filters|Jinja2's built-in filters]]