How to set host_key_checking=false in ansible inventory file?

I would like to use ansible-playbook command instead of ‘vagrant provision‘. However setting host_key_checking=false in the hosts file does not seem to work.

Is there a configuration variable outside of Vagrantfile that can override this value?

^{Due to the fact that I answered this in 2014, I have updated my answer to account for more recent versions of ansible.}

Yes, you can do it at the host/inventory level (Which became possible on newer ansible versions) or global level:

inventory:

Add the following.

host:

Add the following.

hosts/inventory options will work with connection type ssh and not paramiko. Some people may strongly argue that inventory and hosts is more secure because the scope is more limited.

global:

Ansible User Guide – Host Key Checking

• You can do it either in the /etc/ansible/ansible.cfg or ~/.ansible.cfg file:
  
  Default

  [defaults] host_key_checking = False

  1 2 3

  [defaults] host_key_checking = False

• Or you can setup and env variable (this might not work on newer ansible versions):
  
  Default

  export ANSIBLE_HOST_KEY_CHECKING=False

  1 2	export ANSIBLE_HOST_KEY_CHECKING=False