Dynamic Inventory
"""""""""""""""""

Dynamic inventory scripts
=========================
* Ansible supports other inventory sources via an external inventory system
* many inventory scripts are available in the github repo. Here are some examples:

    * zabbix
    * vmware
    * spacewalk
    * openstack
    * nagios
    * gce
    * ec2
    * azure
    * cobbler

* you can write your own inventory script in **any language**

    * return JSON in the right format
    * fill up the the proper arguments


* reload inventory during a playbook run

.. code-block:: yaml

    - name: reload inventory, useful with dynamic inventories when play makes changes to the existing hosts
      cloud_guest:            # this is fake module
        name: newhost
        state: present

    - name: Refresh inventory to ensure new instaces exist in inventory
      meta: refresh_inventory

.. hint::

   Checkout the **tuning** tipps in the Ansible documentation.


How to use dynamic inventory
----------------------------
* Ansible reads the configured ``inventory`` path
* if the file is executable, Ansible will execute it
* as example download a dynmic inventory script e.g ec2.py
* change the permissions -> ``chmod +x``

.. hint::

    It's possible to set a folder as inventroy. And there you can mix static & dynamic inventories.

* a mixed inventory example

.. code-block:: yaml

    inventory/
    ├── [-rwxr-xr-x]  ec2.py
    ├── [-rw-r--r--]  static
    └── [-rwxr-xr-x]  zabbix.py

Links
-----
* http://docs.ansible.com/ansible/intro_dynamic_inventory.html
* https://github.com/ansible/ansible/tree/devel/contrib/inventory
* http://docs.ansible.com/ansible/developing_inventory.html
* http://docs.ansible.com/ansible/developing_inventory.html#tuning-the-external-inventory-script