diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 5a079ea58c4..e09d82a49ac 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -728,6 +728,9 @@ Release 0.23.1 - Unreleased
     into the container request table when multiple hosts for a split happen to
     be on the same rack. (Siddarth Seth via vinodkv)
 
+    MAPREDUCE-3828. Ensure that urls in single-node mode are correct. (sseth
+    via acmurthy) 
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java
index 9d5f891dd98..22b87821f95 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/conf/YarnConfiguration.java
@@ -20,8 +20,13 @@ package org.apache.hadoop.yarn.conf;
 
 import com.google.common.base.Joiner;
 import com.google.common.base.Splitter;
+
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
 import java.util.Iterator;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.net.NetUtils;
 
 public class YarnConfiguration extends Configuration {
   private static final Splitter ADDR_SPLITTER = Splitter.on(':').trimResults();
@@ -543,7 +548,25 @@ public class YarnConfiguration extends Configuration {
     // Use apps manager address to figure out the host for webapp
     addr = conf.get(YarnConfiguration.RM_ADDRESS, YarnConfiguration.DEFAULT_RM_ADDRESS);
     String host = ADDR_SPLITTER.split(addr).iterator().next();
-    return JOINER.join(host, ":", port);
+    String rmAddress = JOINER.join(host, ":", port);
+    InetSocketAddress address = NetUtils.createSocketAddr(
+        rmAddress, DEFAULT_RM_WEBAPP_PORT, RM_WEBAPP_ADDRESS);
+    StringBuffer sb = new StringBuffer();
+    InetAddress resolved = address.getAddress();
+    if (resolved == null || resolved.isAnyLocalAddress() || 
+        resolved.isLoopbackAddress()) {
+      String lh = host;
+      try {
+        lh = InetAddress.getLocalHost().getCanonicalHostName();
+      } catch (UnknownHostException e) {
+        //Ignore and fallback.
+      }
+      sb.append(lh);
+    } else {
+      sb.append(address.getHostName());
+    }
+    sb.append(":").append(address.getPort());
+    return sb.toString();
   }
   
   public static String getRMWebAppURL(Configuration conf) {
diff --git a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/conf/TestYarnConfiguration.java b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/conf/TestYarnConfiguration.java
index d776e630223..5e59fb1bf88 100644
--- a/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/conf/TestYarnConfiguration.java
+++ b/hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/conf/TestYarnConfiguration.java
@@ -1,24 +1,23 @@
 /**
-* Licensed to the Apache Software Foundation (ASF) under one
-* or more contributor license agreements.  See the NOTICE file
-* distributed with this work for additional information
-* regarding copyright ownership.  The ASF licenses this file
-* to you under the Apache License, Version 2.0 (the
-* "License"); you may not use this file except in compliance
-* with the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* Unless required by applicable law or agreed to in writing, software
-* distributed under the License is distributed on an "AS IS" BASIS,
-* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-* See the License for the specific language governing permissions and
-* limitations under the License.
-*/
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 
 package org.apache.hadoop.yarn.conf;
 
-
 import junit.framework.Assert;
 
 import org.apache.hadoop.yarn.conf.YarnConfiguration;
@@ -32,20 +31,25 @@ public class TestYarnConfiguration {
     String rmWebUrl = YarnConfiguration.getRMWebAppURL(conf);
     // shouldn't have a "/" on the end of the url as all the other uri routinnes
     // specifically add slashes and Jetty doesn't handle double slashes.
-    Assert.assertEquals("RM Web Url is not correct", "http://0.0.0.0:8088", 
+    Assert.assertNotSame("RM Web Url is not correct", "http://0.0.0.0:8088",
         rmWebUrl);
   }
 
   @Test
   public void testRMWebUrlSpecified() throws Exception {
     YarnConfiguration conf = new YarnConfiguration();
-    // seems a bit odd but right now we are forcing webapp for RM to be RM_ADDRESS
+    // seems a bit odd but right now we are forcing webapp for RM to be
+    // RM_ADDRESS
     // for host and use the port from the RM_WEBAPP_ADDRESS
-    conf.set(YarnConfiguration.RM_WEBAPP_ADDRESS, "footesting:99110");
+    conf.set(YarnConfiguration.RM_WEBAPP_ADDRESS, "fortesting:24543");
     conf.set(YarnConfiguration.RM_ADDRESS, "rmtesting:9999");
     String rmWebUrl = YarnConfiguration.getRMWebAppURL(conf);
-    Assert.assertEquals("RM Web Url is not correct", "http://rmtesting:99110",
-        rmWebUrl);
+    String[] parts = rmWebUrl.split(":");
+    Assert.assertEquals("RM Web URL Port is incrrect", 24543,
+        Integer.valueOf(parts[parts.length - 1]).intValue());
+    Assert.assertNotSame(
+        "RM Web Url not resolved correctly. Should not be rmtesting",
+        "http://rmtesting:24543", rmWebUrl);
   }
-  
+
 }