override hosts, add reboot if required

playbooks/rebootRequired.yml

@@ -0,0 +1,21 @@
+---
+- name: reboot machine if required
+  # 'all' is okay here, because the fail task will force the user to specify a limit on the command line, using -l or --limit
+  hosts: 'all'
+
+  tasks:
+  - name: checking limit arg
+    fail:
+      msg: "you must use -l or --limit - when you really want to use all hosts, use -l 'all'"
+    when: ansible_limit is not defined
+    run_once: true
+  
+  - name: Check if reboot is required
+    stat:
+      path: /var/run/reboot-required
+    register: reboot_required_file
+
+  - name: Reboot if required
+    become: true
+    reboot:
+    when: reboot_required_file.stat.exists == true