Add the hostname into /etc/hosts.

tasks/hostname.yml

@@ -1,17 +1,24 @@
 ---
-- name: Set the hostname when different from the inventory one.
-  hostname: name={{ hostname }}
-  when: hostname is defined
+- name: hostname | Add entries to /etc/hosts
+  when: custom_etc_hosts_entries | length > 0
   tags: [ 'systemsetup', 'hostname' ]
+  block:
+    - name: hostname | Set the hostname when different from the inventory one.
+      ansible.builtin.hostname:
+        name: "{{ hostname }}"
+      when: hostname is defined
 
-- name: Set the hostname as defined in the inventory
-  hostname: name={{ inventory_hostname  }}
-  when: hostname is not defined
-  tags: [ 'systemsetup', 'hostname' ]
+    - name: hostname | Set the hostname as defined in the inventory
+      ansible.builtin.hostname:
+        name: "{{ inventory_hostname }}"
+      when: hostname is not defined
+
+    - name: hostname | Add the hostname into the /etc/hosts file
+      ansible.builtin.blockinfile:
+        path: /etc/hosts
+        marker_begin: 'ansible_hostname_start'
+        marker_end: 'ansible_hostname_end'
+        marker: "# {mark} hostname entry managed by ansible"
+        block: "{{ ansible_default_ipv4.address }} {{ hostname }} {{ ansible_hostname }}"
+        state: present
 
-- name: Add the hostname to /etc/hosts
-  shell: grep -v {{ ansible_default_ipv4.address }} /etc/hosts > /etc/hosts.tmp ; echo "{{ ansible_default_ipv4.address }} {{ hostname }} {{ ansible_hostname }}" >> /etc/hosts.tmp ; /bin/mv /etc/hosts.tmp /etc/hosts
-  when:
-    - hostname is defined
-    - ansible_virtualization_type == 'xen'
-  tags: [ 'systemsetup', 'hostname' ]