Use cluster_group variable for paths

Instead of trying to automagic this group out of the Ansible hostvars,
just make it explicitly defined in the group_vars to avoid any
confusion.

group_vars/default/base.yml

@@ -1,4 +1,8 @@
 ---
+# The name of the Ansible cluster group, used to set file paths and determine hosts in the cluster
+# This should match the lowest-level group in the Ansible `hosts` file that defines this cluster
+cluster_group: default
+
 # Local timezone for the cluster
 timezone_location: Canada/Eastern
 

roles/base/templates/etc/ntp.conf.j2

@@ -16,7 +16,7 @@ server time.nrc.ca iburst
 server time.chu.nrc.ca iburst
 
 # Local PVC cluster
-{% for host in groups[hostvars[inventory_hostname].group_names[0]] %}
+{% for host in groups[cluster_group] %}
 server {{ host }} iburst
 {% endfor %}
 

roles/pvc/tasks/ceph/bootstrap.yml

@@ -75,7 +75,7 @@
 - name: collect bootstrapped Ceph files into the role
   fetch:
     src: /tmp/ceph-bootstrap/{{ item }}
-    dest: roles/pvc/files/ceph/{{ hostvars[inventory_hostname].group_names[0] }}/ceph/
+    dest: roles/pvc/files/ceph/{{ cluster_group }}/ceph/
     flat: yes
   with_items:
     - ceph.conf

roles/pvc/tasks/ceph/main.yml

@@ -39,7 +39,7 @@
 
 - name: install configurations
   copy:
-    src: ceph/{{ hostvars[inventory_hostname].group_names[0] }}/ceph/{{ item }}
+    src: ceph/{{ cluster_group }}/ceph/{{ item }}
     dest: /etc/ceph/{{ item }}
     owner: ceph
     group: ceph