---
- hosts: all
  become: yes
  vars:
    umbrella: localhost
  pre_tasks:
    - lineinfile:
        dest: /etc/hosts
        line: '127.0.0.1 fruitbar.{{ umbrella }}'
      when: ansible_virtualization_type == "virtualbox"
    - apt:
        update_cache: yes
        cache_valid_time: 3600
  roles:
    - role: fruitbar
...