Introduction

Users must provide two files to Ansible: a inventory listing the managed nodes and a playbook listing the operations to be performed on the managed nodes.

Inventory

The inventory is a YAML in the format

managed_node.com:
  hosts:
    one.managed_node.com:
    two.managed_node.com:

where:

• managed_node.com is the name of the group.

• hosts is a reserved workd.

• one.managed_node.com and two.managed_node.com are the name of the servers.

Variables

The inventory can contain variables and some variables are used to controls how Ansible interacts with the managed node. For example,

• ansible_host configures the IP used when connecting to the managed node.

• ansible_user configures the user name used when connecting to the managed node.

• ansible_password configures the password used when connecting to the managed node.

Warning

The password must not be stored as plain text in the inventory. It is recommended to use vault to store passwords as illustrated in Hello World with Vault.

The inventory would be

managed_node.com:
  hosts:
    one.managed_node.com:
      ansible_user: alice
      ansible_password: 123alice456
    two.managed_node.com:
      ansible_user: bob
      ansible_password: 123bob456

Tip

Variables can also be defined for the group.

managed_node.com:
  hosts:
    one.managed_node.com:
    two.managed_node.com:
  vars:
    ansible_user: alice
    ansible_password: 123alice456

The full list of this variables is in Connecting to hosts: behavioral inventory parameters.

Playbook

The playbook is a YAML with a list of plays, for example

- name: Configure servers
  hosts:
    - managed_node.com
  tasks:
    ...
- name: Start servers
  hosts:
    - managed_node.com
  tasks:
    ...

Tip

It is recommended to use ansible-lint to check the playbook for errors.

To run a playbook, use

ansible-playbook \
--inventory path/to/production.yml \
playbook.yml