Ansible automatically create /etc/hosts file for all host - to give nice short names using dnsmasq

setup-ip.yml

---
- hosts: all
  tasks: []
- hosts: all
  gather_facts: True
  tasks:
  - name: check connection
    ping:
  - name: setup
    setup:
  - name: "Build hosts file"
    lineinfile: dest=/etc/hosts 
                state=present
                dest=/etc/hosts 
                regexp='.*{{ item }}$' line="{{ hostvars[item].ansible_default_ipv4.address }} {{item}}" 
    when: hostvars[item].ansible_default_ipv4.address is defined
    with_items: "{{ groups['all'] }}"
- hosts: localhost
  gather_facts: True
  tasks:
  - name: check connection
    ping:
  - name: setup
    setup:
  - name: "Build hosts file"
    lineinfile: dest=/etc/hosts 
                state=present
                dest=/etc/hosts 
                regexp='.*{{ item }}$' line="{{ hostvars[item].ansible_default_ipv4.address }} {{item}}" 
    when: hostvars[item].ansible_default_ipv4.address is defined
    with_items: "{{ groups['all'] }}"

What if you remove one host from inventory? How are you going to cleanup removed hosts?

Ive switched to a operator concept in 4.x And support sematucs for cleanup

…

Sent from my iPhone

On 1 Jun 2019, at 7:54 AM, Andrey Tkachenko ***@***.***> wrote: What if you remove one host from inventory? How are you going to cleanup removed hosts? — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

Little-bit nasty solution, but it works... (but slow as hell, version: Ansible 2.5.1)

- when: hostvars[item].ansible_default_ipv4.address is defined
+ when: (hostvars[item] is defined) and (hostvars[item]['ansible_default_ipv4'] is defined) and (hostvars[item]['ansible_default_ipv4']['address'] is defined)