diff --git a/xml/resources-1.2.rng b/xml/resources-1.2.rng
index 0ef6066e576..e6e52c32fba 100644
--- a/xml/resources-1.2.rng
+++ b/xml/resources-1.2.rng
@@ -36,6 +36,7 @@
 		  <value>upstart</value>
 		  <value>service</value>
 		  <value>systemd</value>
+		  <value>nagios</value>
 		</choice>
 	      </attribute>
 	    </choice>