First working Ansible playbook file set

ntools/one-m/ansible/group_vars/all

@@ -1,4 +1,5 @@
 ---
-# Variables here are for all host groups
+# ansible/group_vars/all
+# Variables in this file are for *all* host groups (i.e. all hosts)
 
 example_var: 23

ntools/one-m/ansible/one-m-node.yml

@@ -1,9 +1,9 @@
 ---
 # This playbook deploys a BigchainDB node in one machine (one-m).
 
-- name: deploy all software and configure it
+- name: install + configure + start all software
   hosts: all
-  remote_user: root
+  remote_user: ubuntu
 
   roles:
     - common

ntools/one-m/ansible/roles/common/handlers/main.yml

@@ -1,10 +1,9 @@
 ---
-# This file should be in roles - common - handlers
-# Handler to handle common notifications. Handlers are called by other plays.
+# ansible/roles/common/handlers/main.yml
 # See http://docs.ansible.com/playbooks_intro.html for more information about handlers.
 
 - name: restart ntp
   service: name=ntpd state=restarted
 
-- name: restart iptables
-  service: name=iptables state=restarted
+#- name: restart iptables
+#  service: name=iptables state=restarted

ntools/one-m/ansible/roles/common/tasks/main.yml

@@ -1,18 +1,24 @@
 ---
 # ansible/roles/common/tasks/main.yml
+# Note: "become: true" basically means "become root user for this task" i.e. sudo <cmd>
+# See https://docs.ansible.com/ansible/become.html
 
-- name: Do the equivalent of apt-get update
+- name: Do the equivalent of "sudo apt-get update"
   apt: update_cache=yes
+  become: true
 
 - name: Uninstall ntpdate (deprecated)
   apt: name=ntpdate state=absent
+  become: true
   tags: ntp
 
 - name: Update all installed packages to their latest versions
   apt: upgrade=dist
+  become: true
 
 - name: Install ntp
   apt: name=ntp state=latest update_cache=yes
+  become: true
   tags: ntp
 
 #- name: Configure ntp file
@@ -22,7 +28,8 @@
 #  notify: restart ntp
 
 - name: Start the ntp service
-  service: name=ntpd state=started enabled=yes
+  service: name=ntp state=started enabled=yes
+  become: true
   tags: ntp
 
 #- name: test to see if selinux is running