Since Ansible will use openstacksdk as its backend, you will need to ensure that openstacksdk is able to connect to the OpenStack cluster.

To do this, you can change the ~/.config/openstack/clouds.yaml file, ensuring that there is a configuration for the cloud you want to use it for.

An example of what a correct OpenStack credentials set could look like is as follows:

clouds:
  test_cloud:
    region_name: MyRegion
    auth:
      auth_url: http://[YOUR_AUTH_URL_HERE]:5000/v2.0/
      username: [YOUR_USERNAME_HERE]
      password: [YOUR_PASSWORD_HERE]
      project_name: myProject

It's also possible to set a different config file location if you are willing to export the OS_CLIENT_CONFIG_FILE variable as an environment variable.

Now that you have set up the required security so that Ansible can manage your cluster, you can create your first Playbook.