diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index fc921fff0d3..06c2cda558f 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -407,6 +407,9 @@ Release 0.23.0 - Unreleased
     MAPREDUCE-3146. Added a MR specific command line to dump logs for a
     given TaskAttemptID. (Siddharth Seth via vinodkv)
 
+    MAPREDUCE-3275. Added documentation for AM WebApp Proxy. (Robert Evans via
+    acmurthy)
+
   OPTIMIZATIONS
 
     MAPREDUCE-2026. Make JobTracker.getJobCounters() and
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/ClusterSetup.apt.vm b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/ClusterSetup.apt.vm
index 5ce75d21d07..4643faecbd9 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/ClusterSetup.apt.vm
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-site/src/site/apt/ClusterSetup.apt.vm
@@ -100,6 +100,8 @@ Hadoop MapReduce Next Generation - Cluster Setup
 | ResourceManager                      | YARN_RESOURCEMANAGER_OPTS            |
 *--------------------------------------+--------------------------------------+
 | NodeManager                          | YARN_NODEMANAGER_OPTS                |
+*--------------------------------------+--------------------------------------+
+| WebAppProxy                          | YARN_PROXYSERVER_OPTS                |
 *--------------------------------------+--------------------------------------+
 
     For example, To configure Namenode to use parallelGC, the following 
@@ -450,9 +452,16 @@ Hadoop MapReduce Next Generation - Cluster Setup
     Run a script to start NodeManagers on all slaves:
 
 ----
-  $ $YARN_HOME/bin/hdfs start nodemanager --config $HADOOP_CONF_DIR  
+  $ $YARN_HOME/bin/yarn start nodemanager --config $HADOOP_CONF_DIR  
 ----    	  
 
+    Start a standalone WebAppProxy server.  If multiple servers
+    are used with load balancing it should be run on each of them:
+
+----
+  $ $YARN_HOME/bin/yarn start proxyserver --config $HADOOP_CONF_DIR  
+----
+
     Start the MapReduce JobHistory Server with the following command, run on the  
     designated server:
   
@@ -485,9 +494,17 @@ Hadoop MapReduce Next Generation - Cluster Setup
     Run a script to stop NodeManagers on all slaves:
 
 ----
-  $ $YARN_HOME/bin/hdfs stop nodemanager --config $HADOOP_CONF_DIR  
+  $ $YARN_HOME/bin/yarn stop nodemanager --config $HADOOP_CONF_DIR  
 ----    	  
 
+    Stop the WebAppProxy server. If multiple servers are used with load
+    balancing it should be run on each of them:
+
+----
+  $ $YARN_HOME/bin/yarn stop proxyserver --config $HADOOP_CONF_DIR  
+----
+
+
     Stop the MapReduce JobHistory Server with the following command, run on the  
     designated server:
   
@@ -502,7 +519,7 @@ Hadoop MapReduce Next Generation - Cluster Setup
   to run Hadoop in <<secure mode>> with strong, Kerberos-based
   authentication.
       
-  * <<<User Acccounts for Hadoop Daemons>>>
+  * <<<User Accounts for Hadoop Daemons>>>
       
   Ensure that HDFS and YARN daemons run as different Unix users, for e.g.
   <<<hdfs>>> and <<<yarn>>>. Also, ensure that the MapReduce JobHistory
@@ -751,6 +768,31 @@ KVNO Timestamp         Principal
 
     * <<<conf/yarn-site.xml>>>
     
+      * WebAppProxy
+
+      The <<<WebAppProxy>>> provides a proxy between the web applications
+      exported by an application and an end user.  If security is enabled
+      it will warn users before accessing a potentially unsafe web application.
+      Authentication and authorization using the proxy is handled just like
+      any other privileged web application.
+
+*-------------------------+-------------------------+------------------------+
+|| Parameter              || Value                  || Notes                 |
+*-------------------------+-------------------------+------------------------+
+| <<<yarn.web-proxy.address>>> | | |
+| | <<<WebAppProxy>>> host:port for proxy to AM web apps. | |
+| | | <host:port> if this is the same as <<<yarn.resourcemanager.webapp.address>>>|
+| | | or it is not defined then the <<<ResourceManager>>> will run the proxy|
+| | | otherwise a standalone proxy server will need to be launched.|
+*-------------------------+-------------------------+------------------------+
+| <<<yarn.web-proxy.keytab>>> | | |
+| | </etc/security/keytab/web-app.service.keytab> | |
+| | | Kerberos keytab file for the WebAppProxy. |
+*-------------------------+-------------------------+------------------------+
+| <<<yarn.web-proxy.principal>>> | wap/_HOST@REALM.TLD | |
+| | | Kerberos principal name for the WebAppProxy. |
+*-------------------------+-------------------------+------------------------+
+
       * LinuxContainerExecutor
       
       A <<<ContainerExecutor>>> used by YARN framework which define how any
@@ -968,7 +1010,15 @@ KVNO Timestamp         Principal
     Run a script to start NodeManagers on all slaves as <yarn>:
 
 ----
-[yarn]$ $YARN_HOME/bin/hdfs start nodemanager --config $HADOOP_CONF_DIR  
+[yarn]$ $YARN_HOME/bin/yarn start nodemanager --config $HADOOP_CONF_DIR  
+----    	  
+
+    Start a standalone WebAppProxy server. Run on the WebAppProxy 
+    server as <yarn>.  If multiple servers are used with load balancing
+    it should be run on each of them:
+
+----
+[yarn]$ $YARN_HOME/bin/yarn start proxyserver --config $HADOOP_CONF_DIR  
 ----    	  
 
     Start the MapReduce JobHistory Server with the following command, run on the  
@@ -1003,12 +1053,20 @@ KVNO Timestamp         Principal
     Run a script to stop NodeManagers on all slaves as <yarn>:
 
 ----
-[yarn]$ $YARN_HOME/bin/hdfs stop nodemanager --config $HADOOP_CONF_DIR  
+[yarn]$ $YARN_HOME/bin/yarn stop nodemanager --config $HADOOP_CONF_DIR  
 ----    	  
 
+    Stop the WebAppProxy server. Run on the WebAppProxy  server as
+    <yarn>.  If multiple servers are used with load balancing it
+    should be run on each of them:
+
+----
+[yarn]$ $YARN_HOME/bin/yarn stop proxyserver --config $HADOOP_CONF_DIR  
+----
+
     Stop the MapReduce JobHistory Server with the following command, run on the  
     designated server as <mapred>:
-  
+
 ----
 [mapred]$ $YARN_HOME/bin/yarn stop historyserver --config $HADOOP_CONF_DIR  
 ----