--- a/roles/nginx/tasks/easy-rsa.yml	Wed Feb 03 11:56:00 2016 +0800
+++ b/roles/nginx/tasks/easy-rsa.yml	Sun Mar 13 06:23:08 2016 +0000
@@ -9,7 +9,7 @@
   args:
     regexp: '^export KEY_{{ item.key }}="'
     line: 'export KEY_{{ item.key }}="{{ item.value }}"'
-  with_items: munin_ca_vars
+  with_items: '{{ munin_ca_vars }}'
 
 - name: Running clean-all
   shell: . ./vars && ./clean-all
@@ -38,7 +38,7 @@
   args:
     chdir: /etc/nginx/easy-rsa/
     creates: /etc/nginx/easy-rsa/keys/munin.{{ hostname }}.{{ item }}.key
-  with_items: munin_clients
+  with_items: '{{ munin_clients }}'
 
 - name: Export client certificate as a PKCS#12 file
   command: >
@@ -51,9 +51,9 @@
     -passout 'pass:{{ munin_pkcs12_pass }}'
   args:
     creates: /etc/nginx/easy-rsa/keys/munin.{{ hostname }}.{{ item }}.p12
-  with_items: munin_clients
+  with_items: '{{ munin_clients }}'
 
 - name: Fetch the resulting PKCS#12 file
   fetch: src=/etc/nginx/easy-rsa/keys/munin.{{ hostname }}.{{ item }}.p12 dest=./pkcs12/ flat=yes fail_on_missing=yes
-  with_items: munin_clients
+  with_items: '{{ munin_clients }}'
 ...