gistfile1.yml

---
# file: group_vars/dbservers

postgresql_data_dir: /var/lib/pgsql/9.2/data

---
# file: group_vars/dbservers-main

postgresql_role: dbservers-main

---
# file: roles/postgresql/tasks/main.yaml

- name: Install PostgreSQL pg_hba.conf
  copy: src=pg_hba.conf.{{ postgresql_role }} dest={{ postgresql_data_dir }}/pg_hba.conf
  when: inventory_hostname in groups['dbservers-main'] or inventory_hostname in groups['dbservers-test']