---
- user: ansible
  become_user: root
  become: yes
  hosts: debian
  roles: 
    - { role: debian, tags: debian-update } 
    - { role: packages, tags: debian-packages }

- hosts: centos
  gather_facts: yes
  user: ansible
  become_user: root
  become: yes
  roles: 
    - { role: centos, tags: centos-update } 
    - { role: packages, tags: centos-packages }