Simplifying template.

playbooks/roles/rabbitmq/templates/etc/rabbitmq/rabbitmq.config.j2

+% {{ ansible_managed }}
+
+{%- if RABBITMQ_CLUSTERED -%}
+  {%- set hosts= [] -%}
+
+  {%- for host in hostvars.keys() -%}
+    {% do hosts.append("rabbit@ip-" + host.replace('.','-')) %}
+  {%- endfor %}
+
+[{rabbit,
+  [{cluster_nodes, {['{{ hosts|join("\',\'") }}'], disc}}]}].
+
+{%- else -%}
+{# If rabbitmq_clustered_hosts is set, use that instead assuming an aws stack.
+   Note: That these names should include the node name prefix. eg. 'rabbit@hostname'
+#}
+[{rabbit,
+  [{cluster_nodes, {['{{ rabbitmq_clustered_hosts|join("\',\'") }}'], disc}}]}].
+
+{%- endif -%}