Conditional plugin load
diff --git a/collectd/client.sls b/collectd/client.sls
index 355832b..093bc01 100644
--- a/collectd/client.sls
+++ b/collectd/client.sls
@@ -52,8 +52,10 @@
 {%- set grains_fragment_file = service_name+'/meta/collectd.yml' %}
 {%- macro load_grains_file() %}{% include grains_fragment_file %}{% endmacro %}
 {%- set grains_yaml = load_grains_file()|load_yaml %}
+{%- if grains_yaml.plugin is defined %}
 {%- set _dummy = grains.collectd.plugin.update(grains_yaml.plugin) %}
 {%- endif %}
+{%- endif %}
 {%- endfor %}
 
 collectd_client_grain: