svn merge -c 1594263 merging from trunk to branch-2 to fix:HDFS-6334. Client failover proxy provider for IP failover based NN HA. Contributed by Kihwal Lee.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1594264 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -16,6 +16,9 @@ Release 2.5.0 - UNRELEASED
     HDFS-5168. Add cross node dependency support to BlockPlacementPolicy.
     (Nikola Vujic via szetszwo)
 
+    HDFS-6334. Client failover proxy provider for IP failover based NN HA.
+    (kihwal)
+
   IMPROVEMENTS
 
     HDFS-6007. Update documentation about short-circuit local reads (iwasakims

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/HAUtil.java

@@ -37,9 +37,11 @@ import org.apache.hadoop.HadoopIllegalArgumentException;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.NameNodeProxies;
 import org.apache.hadoop.hdfs.protocol.ClientProtocol;
 import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
 import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenSelector;
+import org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.ipc.RPC;
@@ -203,17 +205,54 @@ public class HAUtil {
  
   /**
    * @return true if the given nameNodeUri appears to be a logical URI.
-   * This is the case if there is a failover proxy provider configured
-   * for it in the given configuration.
    */
   public static boolean isLogicalUri(
       Configuration conf, URI nameNodeUri) {
     String host = nameNodeUri.getHost();
+    // A logical name must be one of the service IDs.
+    return DFSUtil.getNameServiceIds(conf).contains(host);
+  }
+
+  /**
+   * Check whether the client has a failover proxy provider configured
+   * for the namenode/nameservice.
+   *
+   * @param conf Configuration
+   * @param nameNodeUri The URI of namenode
+   * @return true if failover is configured.
+   */
+  public static boolean isClientFailoverConfigured(
+      Configuration conf, URI nameNodeUri) {
+    String host = nameNodeUri.getHost();
     String configKey = DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX + "."
         + host;
     return conf.get(configKey) != null;
   }
 
+  /**
+   * Check whether logical URI is needed for the namenode and
+   * the corresponding failover proxy provider in the config.
+   *
+   * @param conf Configuration
+   * @param nameNodeUri The URI of namenode
+   * @return true if logical URI is needed. false, if not needed.
+   * @throws IOException most likely due to misconfiguration.
+   */
+  public static boolean useLogicalUri(Configuration conf, URI nameNodeUri) 
+      throws IOException {
+    // Create the proxy provider. Actual proxy is not created.
+    AbstractNNFailoverProxyProvider<ClientProtocol> provider = NameNodeProxies
+        .createFailoverProxyProvider(conf, nameNodeUri, ClientProtocol.class,
+        false);
+
+    // No need to use logical URI since failover is not configured.
+    if (provider == null) {
+      return false;
+    }
+    // Check whether the failover proxy provider uses logical URI.
+    return provider.useLogicalURI();
+  }
+
   /**
    * Parse the file system URI out of the provided token.
    */

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/NameNodeProxies.java

@@ -50,6 +50,8 @@ import org.apache.hadoop.hdfs.protocolPB.JournalProtocolPB;
 import org.apache.hadoop.hdfs.protocolPB.JournalProtocolTranslatorPB;
 import org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolPB;
 import org.apache.hadoop.hdfs.protocolPB.NamenodeProtocolTranslatorPB;
+import org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider;
+import org.apache.hadoop.hdfs.server.namenode.ha.WrappedFailoverProxyProvider;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.hdfs.server.namenode.SafeModeException;
 import org.apache.hadoop.hdfs.server.protocol.JournalProtocol;
@@ -136,18 +138,15 @@ public class NameNodeProxies {
   @SuppressWarnings("unchecked")
   public static <T> ProxyAndInfo<T> createProxy(Configuration conf,
       URI nameNodeUri, Class<T> xface) throws IOException {
-    Class<FailoverProxyProvider<T>> failoverProxyProviderClass =
+    AbstractNNFailoverProxyProvider<T> failoverProxyProvider =
-        getFailoverProxyProviderClass(conf, nameNodeUri, xface);
+        createFailoverProxyProvider(conf, nameNodeUri, xface, true);
   
-    if (failoverProxyProviderClass == null) {
+    if (failoverProxyProvider == null) {
       // Non-HA case
       return createNonHAProxy(conf, NameNode.getAddress(nameNodeUri), xface,
           UserGroupInformation.getCurrentUser(), true);
     } else {
       // HA case
-      FailoverProxyProvider<T> failoverProxyProvider = NameNodeProxies
-          .createFailoverProxyProvider(conf, failoverProxyProviderClass, xface,
-              nameNodeUri);
       Conf config = new Conf(conf);
       T proxy = (T) RetryProxy.create(xface, failoverProxyProvider,
           RetryPolicies.failoverOnNetworkException(
@@ -155,7 +154,13 @@ public class NameNodeProxies {
               config.maxRetryAttempts, config.failoverSleepBaseMillis,
               config.failoverSleepMaxMillis));
 
-      Text dtService = HAUtil.buildTokenServiceForLogicalUri(nameNodeUri);
+      Text dtService;
+      if (failoverProxyProvider.useLogicalURI()) {
+        dtService = HAUtil.buildTokenServiceForLogicalUri(nameNodeUri);
+      } else {
+        dtService = SecurityUtil.buildTokenService(
+            NameNode.getAddress(nameNodeUri));
+      }
       return new ProxyAndInfo<T>(proxy, dtService);
     }
   }
@@ -183,12 +188,10 @@ public class NameNodeProxies {
       Configuration config, URI nameNodeUri, Class<T> xface,
       int numResponseToDrop) throws IOException {
     Preconditions.checkArgument(numResponseToDrop > 0);
-    Class<FailoverProxyProvider<T>> failoverProxyProviderClass = 
+    AbstractNNFailoverProxyProvider<T> failoverProxyProvider =
-        getFailoverProxyProviderClass(config, nameNodeUri, xface);
+        createFailoverProxyProvider(config, nameNodeUri, xface, true);
-    if (failoverProxyProviderClass != null) { // HA case
+
-      FailoverProxyProvider<T> failoverProxyProvider = 
+    if (failoverProxyProvider != null) { // HA case
-          createFailoverProxyProvider(config, failoverProxyProviderClass, 
-              xface, nameNodeUri);
       int delay = config.getInt(
           DFS_CLIENT_FAILOVER_SLEEPTIME_BASE_KEY,
           DFS_CLIENT_FAILOVER_SLEEPTIME_BASE_DEFAULT);
@@ -211,7 +214,13 @@ public class NameNodeProxies {
       T proxy = (T) Proxy.newProxyInstance(
           failoverProxyProvider.getInterface().getClassLoader(),
           new Class[] { xface }, dummyHandler);
-      Text dtService = HAUtil.buildTokenServiceForLogicalUri(nameNodeUri);
+      Text dtService;
+      if (failoverProxyProvider.useLogicalURI()) {
+        dtService = HAUtil.buildTokenServiceForLogicalUri(nameNodeUri);
+      } else {
+        dtService = SecurityUtil.buildTokenService(
+            NameNode.getAddress(nameNodeUri));
+      }
       return new ProxyAndInfo<T>(proxy, dtService);
     } else {
       LOG.warn("Currently creating proxy using " +
@@ -396,7 +405,7 @@ public class NameNodeProxies {
   /** Gets the configured Failover proxy provider's class */
   @VisibleForTesting
   public static <T> Class<FailoverProxyProvider<T>> getFailoverProxyProviderClass(
-      Configuration conf, URI nameNodeUri, Class<T> xface) throws IOException {
+      Configuration conf, URI nameNodeUri) throws IOException {
     if (nameNodeUri == null) {
       return null;
     }
@@ -408,17 +417,6 @@ public class NameNodeProxies {
       @SuppressWarnings("unchecked")
       Class<FailoverProxyProvider<T>> ret = (Class<FailoverProxyProvider<T>>) conf
           .getClass(configKey, null, FailoverProxyProvider.class);
-      if (ret != null) {
-        // If we found a proxy provider, then this URI should be a logical NN.
-        // Given that, it shouldn't have a non-default port number.
-        int port = nameNodeUri.getPort();
-        if (port > 0 && port != NameNode.DEFAULT_PORT) {
-          throw new IOException("Port " + port + " specified in URI "
-              + nameNodeUri + " but host '" + host
-              + "' is a logical (HA) namenode"
-              + " and does not use port information.");
-        }
-      }
       return ret;
     } catch (RuntimeException e) {
       if (e.getCause() instanceof ClassNotFoundException) {
@@ -433,18 +431,33 @@ public class NameNodeProxies {
 
   /** Creates the Failover proxy provider instance*/
   @VisibleForTesting
-  public static <T> FailoverProxyProvider<T> createFailoverProxyProvider(
+  public static <T> AbstractNNFailoverProxyProvider<T> createFailoverProxyProvider(
-      Configuration conf, Class<FailoverProxyProvider<T>> failoverProxyProviderClass,
+      Configuration conf, URI nameNodeUri, Class<T> xface, boolean checkPort)
-      Class<T> xface, URI nameNodeUri) throws IOException {
+      throws IOException {
+    Class<FailoverProxyProvider<T>> failoverProxyProviderClass = null;
+    AbstractNNFailoverProxyProvider<T> providerNN;
     Preconditions.checkArgument(
         xface.isAssignableFrom(NamenodeProtocols.class),
         "Interface %s is not a NameNode protocol", xface);
     try {
+      // Obtain the class of the proxy provider
+      failoverProxyProviderClass = getFailoverProxyProviderClass(conf,
+          nameNodeUri);
+      if (failoverProxyProviderClass == null) {
+        return null;
+      }
+      // Create a proxy provider instance.
       Constructor<FailoverProxyProvider<T>> ctor = failoverProxyProviderClass
           .getConstructor(Configuration.class, URI.class, Class.class);
       FailoverProxyProvider<T> provider = ctor.newInstance(conf, nameNodeUri,
           xface);
-      return provider;
+
+      // If the proxy provider is of an old implementation, wrap it.
+      if (!(provider instanceof AbstractNNFailoverProxyProvider)) {
+        providerNN = new WrappedFailoverProxyProvider<T>(provider);
+      } else {
+        providerNN = (AbstractNNFailoverProxyProvider<T>)provider;
+      }
     } catch (Exception e) {
       String message = "Couldn't create proxy provider " + failoverProxyProviderClass;
       if (LOG.isDebugEnabled()) {
@@ -456,6 +469,20 @@ public class NameNodeProxies {
         throw new IOException(message, e);
       }
     }
+
+    // Check the port in the URI, if it is logical.
+    if (checkPort && providerNN.useLogicalURI()) {
+      int port = nameNodeUri.getPort();
+      if (port > 0 && port != NameNode.DEFAULT_PORT) {
+        // Throwing here without any cleanup is fine since we have not
+        // actually created the underlying proxies yet.
+        throw new IOException("Port " + port + " specified in URI "
+            + nameNodeUri + " but host '" + nameNodeUri.getHost()
+            + "' is a logical (HA) namenode"
+            + " and does not use port information.");
+      }
+    }
+    return providerNN;
   }
 
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/web/resources/DatanodeWebHdfsMethods.java

@@ -127,8 +127,8 @@ public class DatanodeWebHdfsMethods {
     token.decodeFromUrlString(delegation);
     URI nnUri = URI.create(HdfsConstants.HDFS_URI_SCHEME +
             "://" + nnId);
-    boolean isHA = HAUtil.isLogicalUri(conf, nnUri);
+    boolean isLogical = HAUtil.isLogicalUri(conf, nnUri);
-    if (isHA) {
+    if (isLogical) {
       token.setService(HAUtil.buildTokenServiceForLogicalUri(nnUri));
     } else {
       token.setService(SecurityUtil.buildTokenService(nnUri));

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ha/AbstractNNFailoverProxyProvider.java

@@ -0,0 +1,35 @@
+/**
+ * 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.hdfs.server.namenode.ha;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.io.retry.FailoverProxyProvider;
+
+public abstract class AbstractNNFailoverProxyProvider<T> implements
+   FailoverProxyProvider <T> {
+
+  /**
+   * Inquire whether logical HA URI is used for the implementation. If it is
+   * used, a special token handling may be needed to make sure a token acquired 
+   * from a node in the HA pair can be used against the other node. 
+   *
+   * @return true if logical HA URI is used. false, if not used.
+   */
+  public abstract boolean useLogicalURI(); 
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ha/ConfiguredFailoverProxyProvider.java

@@ -34,8 +34,8 @@ import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
 import org.apache.hadoop.hdfs.HAUtil;
 import org.apache.hadoop.hdfs.NameNodeProxies;
+import org.apache.hadoop.hdfs.server.namenode.ha.AbstractNNFailoverProxyProvider;
 import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
-import org.apache.hadoop.io.retry.FailoverProxyProvider;
 import org.apache.hadoop.ipc.RPC;
 import org.apache.hadoop.security.UserGroupInformation;
 
@@ -46,8 +46,8 @@ import com.google.common.base.Preconditions;
  * to connect to during fail-over. The first configured address is tried first,
  * and on a fail-over event the other address is tried.
  */
-public class ConfiguredFailoverProxyProvider<T> implements
+public class ConfiguredFailoverProxyProvider<T> extends
-    FailoverProxyProvider<T> {
+    AbstractNNFailoverProxyProvider<T> {
   
   private static final Log LOG =
       LogFactory.getLog(ConfiguredFailoverProxyProvider.class);
@@ -165,4 +165,12 @@ public class ConfiguredFailoverProxyProvider<T> implements
       }
     }
   }
+
+  /**
+   * Logical URI is required for this failover proxy provider.
+   */
+  @Override
+  public boolean useLogicalURI() {
+    return true;
+  }
 }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ha/IPFailoverProxyProvider.java

@@ -0,0 +1,133 @@
+/**
+ * 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.hdfs.server.namenode.ha;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.URI;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.NameNodeProxies;
+import org.apache.hadoop.hdfs.server.namenode.NameNode;
+import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
+import org.apache.hadoop.io.retry.FailoverProxyProvider;
+import org.apache.hadoop.ipc.RPC;
+import org.apache.hadoop.security.UserGroupInformation;
+
+import com.google.common.base.Preconditions;
+
+/**
+ * A NNFailoverProxyProvider implementation which works on IP failover setup.
+ * Only one proxy is used to connect to both servers and switching between
+ * the servers is done by the environment/infrastructure, which guarantees
+ * clients can consistently reach only one node at a time.
+ *
+ * Clients with a live connection will likely get connection reset after an
+ * IP failover. This case will be handled by the 
+ * FailoverOnNetworkExceptionRetry retry policy. I.e. if the call is
+ * not idempotent, it won't get retried.
+ *
+ * A connection reset while setting up a connection (i.e. before sending a
+ * request) will be handled in ipc client.
+ *
+ * The namenode URI must contain a resolvable host name.
+ */
+public class IPFailoverProxyProvider<T> extends
+    AbstractNNFailoverProxyProvider<T> {
+  private final Configuration conf;
+  private final Class<T> xface;
+  private final URI nameNodeUri;
+  private ProxyInfo<T> nnProxyInfo = null;
+  
+  public IPFailoverProxyProvider(Configuration conf, URI uri,
+      Class<T> xface) {
+    Preconditions.checkArgument(
+        xface.isAssignableFrom(NamenodeProtocols.class),
+        "Interface class %s is not a valid NameNode protocol!");
+    this.xface = xface;
+    this.nameNodeUri = uri;
+
+    this.conf = new Configuration(conf);
+    int maxRetries = this.conf.getInt(
+        DFSConfigKeys.DFS_CLIENT_FAILOVER_CONNECTION_RETRIES_KEY,
+        DFSConfigKeys.DFS_CLIENT_FAILOVER_CONNECTION_RETRIES_DEFAULT);
+    this.conf.setInt(
+        CommonConfigurationKeysPublic.IPC_CLIENT_CONNECT_MAX_RETRIES_KEY,
+        maxRetries);
+    
+    int maxRetriesOnSocketTimeouts = this.conf.getInt(
+        DFSConfigKeys.DFS_CLIENT_FAILOVER_CONNECTION_RETRIES_ON_SOCKET_TIMEOUTS_KEY,
+        DFSConfigKeys.DFS_CLIENT_FAILOVER_CONNECTION_RETRIES_ON_SOCKET_TIMEOUTS_DEFAULT);
+    this.conf.setInt(
+        CommonConfigurationKeysPublic.IPC_CLIENT_CONNECT_MAX_RETRIES_ON_SOCKET_TIMEOUTS_KEY,
+        maxRetriesOnSocketTimeouts);
+  }
+    
+  @Override
+  public Class<T> getInterface() {
+    return xface;
+  }
+
+  @Override
+  public synchronized ProxyInfo<T> getProxy() {
+    // Create a non-ha proxy if not already created.
+    if (nnProxyInfo == null) {
+      try {
+        // Create a proxy that is not wrapped in RetryProxy
+        InetSocketAddress nnAddr = NameNode.getAddress(nameNodeUri);
+        nnProxyInfo = new ProxyInfo<T>(NameNodeProxies.createNonHAProxy(
+            conf, nnAddr, xface, UserGroupInformation.getCurrentUser(), 
+            false).getProxy(), nnAddr.toString());
+      } catch (IOException ioe) {
+        throw new RuntimeException(ioe);
+      }
+    }
+    return nnProxyInfo;
+  }
+
+  /** Nothing to do for IP failover */
+  @Override
+  public void performFailover(T currentProxy) {
+  }
+
+  /**
+   * Close the proxy,
+   */
+  @Override
+  public synchronized void close() throws IOException {
+    if (nnProxyInfo == null) {
+      return;
+    }
+    if (nnProxyInfo.proxy instanceof Closeable) {
+      ((Closeable)nnProxyInfo.proxy).close();
+    } else {
+      RPC.stopProxy(nnProxyInfo.proxy);
+    }
+  }
+
+  /**
+   * Logical URI is not used for IP failover.
+   */
+  @Override
+  public boolean useLogicalURI() {
+    return false;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/ha/WrappedFailoverProxyProvider.java

@@ -0,0 +1,80 @@
+/**
+ * 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.hdfs.server.namenode.ha;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.URI;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
+import org.apache.hadoop.io.retry.FailoverProxyProvider;
+import org.apache.hadoop.ipc.RPC;
+import org.apache.hadoop.security.UserGroupInformation;
+
+import com.google.common.base.Preconditions;
+
+/**
+ * A NNFailoverProxyProvider implementation which wrapps old implementations
+ * directly implementing the {@link FailoverProxyProvider} interface.
+ *
+ * It is assumed that the old impelmentation is using logical URI.
+ */
+public class WrappedFailoverProxyProvider<T> extends
+    AbstractNNFailoverProxyProvider<T> {
+  private final FailoverProxyProvider<T> proxyProvider;
+  
+  /**
+   * Wrap the given instance of an old FailoverProxyProvider.
+   */
+  public WrappedFailoverProxyProvider(FailoverProxyProvider<T> provider) {
+    proxyProvider = provider;
+  }
+    
+  @Override
+  public Class<T> getInterface() {
+    return proxyProvider.getInterface();
+  }
+
+  @Override
+  public synchronized ProxyInfo<T> getProxy() {
+    return proxyProvider.getProxy();
+  }
+
+  @Override
+  public void performFailover(T currentProxy) {
+    proxyProvider.performFailover(currentProxy);
+  }
+
+  /**
+   * Close the proxy,
+   */
+  @Override
+  public synchronized void close() throws IOException {
+    proxyProvider.close();
+  }
+
+  /**
+   * Assume logical URI is used for old proxy provider implementations.
+   */
+  @Override
+  public boolean useLogicalURI() {
+    return true;
+  }
+}

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/DFSAdmin.java

@@ -913,9 +913,10 @@ public class DFSAdmin extends FsShell {
     
     Configuration dfsConf = dfs.getConf();
     URI dfsUri = dfs.getUri();
-    boolean isHaEnabled = HAUtil.isLogicalUri(dfsConf, dfsUri);
+    boolean isHaAndLogicalUri = HAUtil.isLogicalUri(dfsConf, dfsUri);
-    if (isHaEnabled) {
+    if (isHaAndLogicalUri) {
-      // In the case of HA, run finalizeUpgrade for all NNs in this nameservice
+      // In the case of HA and logical URI, run finalizeUpgrade for all
+      // NNs in this nameservice.
       String nsId = dfsUri.getHost();
       List<ClientProtocol> namenodes =
           HAUtil.getProxiesForAllNameNodesInNameservice(dfsConf, nsId);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/web/WebHdfsFileSystem.java

@@ -176,10 +176,13 @@ public class WebHdfsFileSystem extends FileSystem
     this.uri = URI.create(uri.getScheme() + "://" + uri.getAuthority());
     this.nnAddrs = resolveNNAddr();
 
-    boolean isHA = HAUtil.isLogicalUri(conf, this.uri);
+    boolean isHA = HAUtil.isClientFailoverConfigured(conf, this.uri);
-    // In non-HA case, the code needs to call getCanonicalUri() in order to
+    boolean isLogicalUri = isHA && HAUtil.isLogicalUri(conf, this.uri);
-    // handle the case where no port is specified in the URI
+    // In non-HA or non-logical URI case, the code needs to call
-    this.tokenServiceName = isHA ? HAUtil.buildTokenServiceForLogicalUri(uri)
+    // getCanonicalUri() in order to handle the case where no port is
+    // specified in the URI
+    this.tokenServiceName = isLogicalUri ?
+        HAUtil.buildTokenServiceForLogicalUri(uri)
         : SecurityUtil.buildTokenService(getCanonicalUri());
     initializeTokenAspect();
 
@@ -1095,8 +1098,8 @@ public class WebHdfsFileSystem extends FileSystem
   /**
    * Resolve an HDFS URL into real INetSocketAddress. It works like a DNS
    * resolver when the URL points to an non-HA cluster. When the URL points to
-   * an HA cluster, the resolver further resolves the logical name (i.e., the
+   * an HA cluster with its logical name, the resolver further resolves the
-   * authority in the URL) into real namenode addresses.
+   * logical name(i.e., the authority in the URL) into real namenode addresses.
    */
   private InetSocketAddress[] resolveNNAddr() throws IOException {
     Configuration conf = getConf();

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSClientFailover.java

@@ -19,6 +19,7 @@ package org.apache.hadoop.hdfs;
 
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -41,12 +42,17 @@ import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
 import org.apache.hadoop.fs.FileContext;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.HAUtil;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider;
+import org.apache.hadoop.hdfs.server.namenode.ha.IPFailoverProxyProvider;
 import org.apache.hadoop.hdfs.server.namenode.ha.HATestUtil;
 import org.apache.hadoop.io.IOUtils;
+import org.apache.hadoop.io.retry.DefaultFailoverProxyProvider;
+import org.apache.hadoop.io.retry.FailoverProxyProvider;
 import org.apache.hadoop.net.ConnectTimeoutException;
 import org.apache.hadoop.net.StandardSocketFactory;
+import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.util.StringUtils;
 import org.hamcrest.BaseMatcher;
@@ -172,12 +178,12 @@ public class TestDFSClientFailover {
    */
   @Test
   public void testLogicalUriShouldNotHavePorts() {
-    Configuration conf = new HdfsConfiguration();
+    Configuration config = new HdfsConfiguration(conf);
-    conf.set(DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX + ".foo",
+    String logicalName = HATestUtil.getLogicalHostname(cluster);
-        ConfiguredFailoverProxyProvider.class.getName());
+    HATestUtil.setFailoverConfigurations(cluster, config, logicalName);
-    Path p = new Path("hdfs://foo:12345/");
+    Path p = new Path("hdfs://" + logicalName + ":12345/");
     try {
-      p.getFileSystem(conf).exists(p);
+      p.getFileSystem(config).exists(p);
       fail("Did not fail with fake FS");
     } catch (IOException ioe) {
       GenericTestUtils.assertExceptionContains(
@@ -278,4 +284,72 @@ public class TestDFSClientFailover {
     // Ensure that the logical hostname was never resolved.
     Mockito.verify(spyNS, Mockito.never()).lookupAllHostAddr(Mockito.eq(logicalHost));
   }
+
+  /** Dummy implementation of plain FailoverProxyProvider */
+  public static class DummyLegacyFailoverProxyProvider<T>
+      implements FailoverProxyProvider<T> {
+    private Class<T> xface;
+    private T proxy;
+    public DummyLegacyFailoverProxyProvider(Configuration conf, URI uri,
+        Class<T> xface) {
+      try {
+        this.proxy = NameNodeProxies.createNonHAProxy(conf,
+            NameNode.getAddress(uri), xface,
+            UserGroupInformation.getCurrentUser(), false).getProxy();
+        this.xface = xface;
+      } catch (IOException ioe) {
+      }
+    }
+
+    @Override
+    public Class<T> getInterface() {
+      return xface;
+    }
+
+    @Override
+    public ProxyInfo<T> getProxy() {
+      return new ProxyInfo<T>(proxy, "dummy");
+    }
+
+    @Override
+    public void performFailover(T currentProxy) {
+    }
+
+    @Override
+    public void close() throws IOException {
+    }
+  }
+
+  /**
+   * Test to verify legacy proxy providers are correctly wrapped.
+   */
+  public void testWrappedFailoverProxyProvider() throws Exception {
+    // setup the config with the dummy provider class
+    Configuration config = new HdfsConfiguration(conf);
+    String logicalName = HATestUtil.getLogicalHostname(cluster);
+    HATestUtil.setFailoverConfigurations(cluster, config, logicalName);
+    config.set(DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX + "." + logicalName,
+        DummyLegacyFailoverProxyProvider.class.getName());
+    Path p = new Path("hdfs://" + logicalName + "/");
+
+    // Logical URI should be used.
+    assertTrue("Legacy proxy providers should use logical URI.",
+        HAUtil.useLogicalUri(config, p.toUri()));
+  }
+
+  /**
+   * Test to verify IPFailoverProxyProvider is not requiring logical URI.
+   */
+  public void testIPFailoverProxyProviderLogicalUri() throws Exception {
+    // setup the config with the IP failover proxy provider class
+    Configuration config = new HdfsConfiguration(conf);
+    URI nnUri = cluster.getURI(0);
+    config.set(DFS_CLIENT_FAILOVER_PROXY_PROVIDER_KEY_PREFIX + "." +
+        nnUri.getHost(),
+        IPFailoverProxyProvider.class.getName());
+
+    assertFalse("IPFailoverProxyProvider should not use logical URI.",
+        HAUtil.useLogicalUri(config, nnUri));
+  }
+
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestRetryCacheWithHA.java

@@ -188,12 +188,9 @@ public class TestRetryCacheWithHA {
   
   private DFSClient genClientWithDummyHandler() throws IOException {
     URI nnUri = dfs.getUri();
-    Class<FailoverProxyProvider<ClientProtocol>> failoverProxyProviderClass = 
-        NameNodeProxies.getFailoverProxyProviderClass(conf, nnUri, 
-            ClientProtocol.class);
     FailoverProxyProvider<ClientProtocol> failoverProxyProvider = 
         NameNodeProxies.createFailoverProxyProvider(conf, 
-            failoverProxyProviderClass, ClientProtocol.class, nnUri);
+            nnUri, ClientProtocol.class, true);
     InvocationHandler dummyHandler = new DummyRetryInvocationHandler(
         failoverProxyProvider, RetryPolicies
         .failoverOnNetworkException(RetryPolicies.TRY_ONCE_THEN_FAIL,