machines. The generated inventory file is stored as part of your local Vagrant environment in `.vagrant/provisioners/ansible/inventory/vagrant_ansible_inventory`.
The second option is for situations where you'd like to have more control over the inventory management.
With the `ansible.inventory_path` option, you can reference a specific inventory resource (e.g. a static inventory file, a [dynamic inventory script](http://docs.ansible.com/intro_dynamic_inventory.html) or even [multiple inventories stored in the same directory](http://docs.ansible.com/intro_dynamic_inventory.html#using-multiple-inventory-sources)). Vagrant will then use this inventory information instead of generating it.
*`ansible.extra_vars` can be used to pass additional variables (with highest priority) to the playbook. This parameter can be a path to a JSON or YAML file, or a hash. For example:
*`ansible.limit` can be set to a string or an array of machines or groups from the inventory file to further control which hosts are affected. Note that:
* As of Vagrant 1.5, the machine name (taken from Vagrantfile) is set as **default limit** to ensure that `vagrant provision` steps only affect the expected machine. Setting `ansible.limit` will override this default.
* Setting `ansible.limit = 'all'` can be used to make Ansible connect to all machines from the inventory file.
*`ansible.raw_arguments` can be set to an array of strings corresponding to a list of `ansible-playbook` arguments (e.g. `['--check', '-M /my/modules']`). It is an *unsafe wildcard* that can be used to apply Ansible options that are not (yet) supported by this Vagrant provisioner. Following precedence rules apply:
*`ansible.raw_ssh_args` can be set to an array of strings corresponding to a list of OpenSSH client parameters (e.g. `['-o ControlMaster=no']`). It is an *unsafe wildcard* that can be used to pass additional SSH settings to Ansible via `ANSIBLE_SSH_ARGS` environment variable.
*`ansible.host_key_checking` can be set to `true` which will enable host key checking. As Vagrant 1.5, the default value is `false`, to avoid connection problems when creating new virtual machines.
Vagrant is designed to provision [multi-machine environments](/v2/multi-machine) in sequence, but the following configuration pattern can be used to take advantage of Ansible parallelism:
Certain settings in Ansible are (only) adjustable via a [configuration file](http://docs.ansible.com/intro_configuration.html), and you might want to ship such a file in your Vagrant project.
As `ansible-playbook` command looks for local `ansible.cfg` configuration file in its *current directory* (but not in the directory that contains the main playbook), you have to store this file adjacent to your Vagrantfile.
Note that it is also possible to reference an Ansible configuration file via `ANSIBLE_CONFIG` environment variable, if you want to be flexible about the location of this file.
It is good to know that following Ansible settings always override the `config.ssh.username` option defined in [Vagrant SSH Settings](/v2/vagrantfile/ssh_settings.html):
Be aware that copying snippets from the Ansible documentation might lead to this problem, as `root` is used as the remote user in many [examples](http://docs.ansible.com/playbooks_intro.html#hosts-and-users).
fatal: [ansible-devbox] => SSH encountered an unknown error. We recommend you re-run the command using -vvvv, which will enable SSH debugging output to help diagnose the issue.