gistfile1.yml

---
- hosts:
    - servers
  vars:
    ansible_ssh_user: root
  tasks:
    - name: make sure local keys directory exists
      local_action: file path=./keys state=directory
    - name: check key pair exists
      local_action: command test -f keys/id_rsa
      failed_when: false
      register: key_pair_exists
      changed_when: key_pair_exists.rc != 0
    - name: generating ssh key pair
      local_action: shell ssh-keygen -t rsa -f keys/id_rsa -N ""
      when: key_pair_exists|changed