Install Ansible >= 2.8
https://docs.ansible.com/ansible/2.8/installation_guide/intro_installation.html
Control node needs to have ssh key-auth access to all nodes, including tank, cassandra, proxy and later on memcached nodes
ansible-playbook -i hosts site.yml
ansible-playbook -i hosts tank_nodes.yml
The Prometheus Node Exporter is installed on all nodes, the version can be controlled using the variables for its ragarding role.
TODO: describe roles