playbook-hosts.yml

---
- hosts: all
  become: true
  vars:
    internal_domain: example.org
  tasks:
   - name: setting hostname from inventory
     hostname: name="{{ inventory_hostname }}.{{ internal_domain }}"

   # better idea to manage /etc/hosts from inventory.ini
   - name: set changes to /etc/hosts to resolve dns dependency
     blockinfile:
       dest: /etc/hosts
       block: |
         10.64.32.1     database-master    database-master.{{ internal_domain }}
         10.64.64.1     database-backup    database-backup.{{ internal_domain }}
         10.64.128.10   monitor-server-1   monitor-server-1.{{ internal_domain }}
         10.64.228.10   monitor-server-2   monitor-server-2.{{ internal_domain }}
         10.64.128.20   rsyslog-server-1   rsyslog-server-1.{{ internal_domain }}
         10.64.228.20   rsyslog-server-2   rsyslog-server-2.{{ internal_domain }}
         10.64.128.20   ssh-proxy-host-1   ssh-proxy-host-1.{{ internal_domain }}
         10.64.228.20   ssh-proxy-host-2   ssh-proxy-host-2.{{ internal_domain }}