---
- hosts: all
  roles:
    - base-common
    - rsyslog-common

- hosts: collector.aurore.local
  roles:
    - rsyslog-collector

- hosts: elastic.aurore.local
  roles:
    - elasticsearch
    - logstash
    - redis
    - kibana

- hosts: pki.aurore.local
  roles:
    - openssl-ca
...