diff --git a/hadoop-yarn-project/CHANGES.txt b/hadoop-yarn-project/CHANGES.txt
index b72c648bc1a..eb271527665 100644
--- a/hadoop-yarn-project/CHANGES.txt
+++ b/hadoop-yarn-project/CHANGES.txt
@@ -196,6 +196,9 @@ Release 2.8.0 - UNRELEASED
 
     YARN-2784. Make POM project names consistent. (Rohith via devaraj)
 
+    YARN-20. More information for "yarn.resourcemanager.webapp.address" in 
+    yarn-default.xml (Bartosz Ługowski vai tgraves)
+
   OPTIMIZATIONS
 
     YARN-3339. TestDockerContainerExecutor should pull a single image and not
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml
index 5d0f07d8f5d..e1e0ebd3d77 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/resources/yarn-default.xml
@@ -111,13 +111,21 @@
   </property>
 
   <property>
-    <description>The http address of the RM web application.</description>
+    <description>
+      The http address of the RM web application.
+      If only a host is provided as the value,
+      the webapp will be served on a random port.
+    </description>
     <name>yarn.resourcemanager.webapp.address</name>
     <value>${yarn.resourcemanager.hostname}:8088</value>
   </property>
 
   <property>
-    <description>The https adddress of the RM web application.</description>
+    <description>
+      The https address of the RM web application.
+      If only a host is provided as the value,
+      the webapp will be served on a random port.
+    </description>
     <name>yarn.resourcemanager.webapp.https.address</name>
     <value>${yarn.resourcemanager.hostname}:8090</value>
   </property>