Fix

  become: yes

  roles:

    - hostname

- hosts: ipaserver:ipareplicas

  tasks:

    - name: Populate /etc/hosts

      lineinfile:

        dest: /etc/hosts

        regexp: '.*{{ item }}$'

        line: "{{ hostvars[item].ansible_default_ipv4.address }} {{item}}"

        state: present

      when: hostvars[item].ansible_default_ipv4.address is defined

      with_items: groups['ipaserver','ipareplicas']

#

#- hosts: ipaserver:ipareplicas

#  tasks:

#    - name: Populate /etc/hosts

#      lineinfile:

#        dest: /etc/hosts

#        regexp: '.*{{ item }}$'

#        line: "{{ hostvars[item].ansible_default_ipv4.address }} {{item}}"

#        state: present

#      when: hostvars[item].ansible_default_ipv4.address is defined

#      with_items: groups['ipaserver','ipareplicas']