iiab/roles/0-init/tasks/hostname.yml

- name: Does /etc/cloud/cloud.cfg exist e.g. is this Ubuntu Server 18+ ?
  stat:
    path: /etc/cloud/cloud.cfg
  register: cloudcfg_test

- name: "If so, ensure 'preserve_hostname: true' is in /etc/cloud/cloud.cfg"
  lineinfile:
    path: /etc/cloud/cloud.cfg
    regexp: '^preserve_hostname*'
    line: 'preserve_hostname: true'
    state: present
  when: cloudcfg_test.stat.exists

- name: 'Set /etc/hostname by running: hostnamectl set-hostname "{{ iiab_hostname }}"'
  command: hostnamectl set-hostname "{{ iiab_hostname }}"
  # 2021-08-31: Periods in /etc/hostname fail with some WiFi routers (#2904)
  # command: hostnamectl set-hostname "{{ iiab_hostname }}.{{ iiab_domain }}"

#- name: Install /etc/sysconfig/network from template (redhat)
#  template:
#    src: roles/network/templates/network/sysconfig.network.j2
#    dest: /etc/sysconfig/network
#    owner: root
#    group: root
#    mode: 0644
#  when: is_redhat

# roles/network/tasks/hosts.yml [no longer in use] ALSO did this:
- name: 'Put FQDN & hostnames in /etc/hosts: "127.0.0.1 {{ iiab_hostname }}.{{ iiab_domain }} localhost.localdomain localhost {{ iiab_hostname }} box box.lan"'
  lineinfile:
    path: /etc/hosts
    regexp: '^127\.0\.0\.1'
    line: '127.0.0.1     {{ iiab_hostname }}.{{ iiab_domain }} localhost.localdomain localhost {{ iiab_hostname }} box box.lan'
    #owner: root
    #group: root
    #mode: 0644

#- name: Re-configuring httpd - not initial install
#  include_tasks: roles/httpd/tasks/main.yml
#  when: iiab_stage|int > 3

#- name: Re-configuring rest of networking - not initial install
#  include_tasks: roles/network/tasks/main.yml
#  when: iiab_stage|int > 4