HBASE-5179 Handle potential data loss due to concurrent processing of processFaileOver and ServerShutdownHandler

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1300194 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/hadoop/hbase/master/AssignmentManager.java

@@ -65,7 +65,6 @@ import org.apache.hadoop.hbase.executor.EventHandler.EventType;
 import org.apache.hadoop.hbase.executor.ExecutorService;
 import org.apache.hadoop.hbase.executor.RegionTransitionData;
 import org.apache.hadoop.hbase.ipc.ServerNotRunningYetException;
-import org.apache.hadoop.hbase.master.AssignmentManager.RegionState;
 import org.apache.hadoop.hbase.master.AssignmentManager.RegionState.State;
 import org.apache.hadoop.hbase.master.handler.ClosedRegionHandler;
 import org.apache.hadoop.hbase.master.handler.DisableTableHandler;
@@ -328,11 +327,13 @@ public class AssignmentManager extends ZooKeeperListener {
   /**
    * Called on startup.
    * Figures whether a fresh cluster start of we are joining extant running cluster.
+   * @param onlineServers onlined servers when master started
    * @throws IOException
    * @throws KeeperException
    * @throws InterruptedException
    */
-  void joinCluster() throws IOException, KeeperException, InterruptedException {
+  void joinCluster(final Set<ServerName> onlineServers) throws IOException,
+      KeeperException, InterruptedException {
     // Concurrency note: In the below the accesses on regionsInTransition are
     // outside of a synchronization block where usually all accesses to RIT are
     // synchronized.  The presumption is that in this case it is safe since this
@@ -343,7 +344,7 @@ public class AssignmentManager extends ZooKeeperListener {
 
     // Scan META to build list of existing regions, servers, and assignment
     // Returns servers who have not checked in (assumed dead) and their regions
-    Map<ServerName,List<Pair<HRegionInfo,Result>>> deadServers = rebuildUserRegions();
+    Map<ServerName, List<Pair<HRegionInfo, Result>>> deadServers = rebuildUserRegions(onlineServers);
 
     processDeadServersAndRegionsInTransition(deadServers);
 
@@ -353,6 +354,16 @@ public class AssignmentManager extends ZooKeeperListener {
     recoverTableInEnablingState(this.enablingTables, isWatcherCreated);
   }
 
+  /**
+   * Only used for tests
+   * @throws IOException
+   * @throws KeeperException
+   * @throws InterruptedException
+   */
+  void joinCluster() throws IOException, KeeperException, InterruptedException {
+    joinCluster(serverManager.getOnlineServers().keySet());
+  }
+
   /**
    * Process all regions that are in transition up in zookeeper.  Used by
    * master joining an already running cluster.
@@ -398,6 +409,12 @@ public class AssignmentManager extends ZooKeeperListener {
       }
     }
 
+    // Remove regions in RIT, they are possibly being processed by
+    // ServerShutdownHandler.
+    synchronized (regionsInTransition) {
+      nodes.removeAll(regionsInTransition.keySet());
+    }
+
     // If we found user regions out on cluster, its a failover.
     if (this.failover) {
       LOG.info("Found regions out on cluster or in RIT; failover");
@@ -1770,6 +1787,7 @@ public class AssignmentManager extends ZooKeeperListener {
     final List<ServerName> servers = this.serverManager.getOnlineServersList();
     final List<ServerName> drainingServers = this.serverManager.getDrainingServersList();
 
+
     if (serverToExclude != null) servers.remove(serverToExclude);
 
     // Loop through the draining server list and remove them from the server
@@ -1782,6 +1800,11 @@ public class AssignmentManager extends ZooKeeperListener {
       }
     }
 
+    // Remove the deadNotExpired servers from the server list.
+    removeDeadNotExpiredServers(servers);
+
+
+
     if (servers.isEmpty()) return null;
 
     RegionPlan randomPlan = new RegionPlan(state.getRegion(), null,
@@ -1813,7 +1836,7 @@ public class AssignmentManager extends ZooKeeperListener {
         " so generated a random one; " + randomPlan + "; " +
         serverManager.countOfRegionServers() +
                " (online=" + serverManager.getOnlineServers().size() +
-               ", exclude=" + drainingServers.size() + ") available servers");
+               ", available=" + servers.size() + ") available servers");
         return randomPlan;
       }
     LOG.debug("Using pre-existing plan for region " +
@@ -1821,6 +1844,23 @@ public class AssignmentManager extends ZooKeeperListener {
       return existingPlan;
   }
 
+  /**
+   * Loop through the deadNotExpired server list and remove them from the
+   * servers.
+   * @param servers
+   */
+  public void removeDeadNotExpiredServers(List<ServerName> servers) {
+    Set<ServerName> deadNotExpiredServers = this.serverManager
+        .getDeadNotExpiredServers();
+    if (!deadNotExpiredServers.isEmpty()) {
+      for (ServerName server : deadNotExpiredServers) {
+        LOG.debug("Removing dead but not expired server: " + server
+            + " from eligible server pool.");
+        servers.remove(server);
+      }
+    }
+  }
+
   /**
    * Unassign the list of regions. Configuration knobs:
    * hbase.bulk.waitbetween.reopen indicates the number of milliseconds to
@@ -2134,6 +2174,7 @@ public class AssignmentManager extends ZooKeeperListener {
       throws IOException,
       InterruptedException {
     List<ServerName> servers = this.serverManager.getOnlineServersList();
+    removeDeadNotExpiredServers(servers);
     assignUserRegions(regions, servers);
   }
 
@@ -2173,6 +2214,9 @@ public class AssignmentManager extends ZooKeeperListener {
     // Get all available servers
     List<ServerName> servers = serverManager.getOnlineServersList();
 
+    // Remove the deadNotExpired servers from the server list.
+    removeDeadNotExpiredServers(servers);
+
     // If there are no servers we need not proceed with region assignment.
     if(servers.isEmpty()) return;
 
@@ -2377,11 +2421,14 @@ public class AssignmentManager extends ZooKeeperListener {
    * <p>
    * Returns a map of servers that are not found to be online and the regions
    * they were hosting.
+   * @param onlineServers if one region's location belongs to onlineServers, it
+   *          doesn't need to be assigned.
    * @return map of servers not online to their assigned regions, as stored
    *         in META
    * @throws IOException
    */
-  Map<ServerName, List<Pair<HRegionInfo, Result>>> rebuildUserRegions()
+  Map<ServerName, List<Pair<HRegionInfo, Result>>> rebuildUserRegions(
+      final Set<ServerName> onlineServers)
   throws IOException, KeeperException {
     // Region assignment from META
     List<Result> results = MetaReader.fullScan(this.catalogTracker);
@@ -2414,7 +2461,7 @@ public class AssignmentManager extends ZooKeeperListener {
         }
         addTheTablesInPartialState(this.disablingTables, this.enablingTables, regionInfo,
             tableName);
-      } else if (!this.serverManager.isServerOnline(regionLocation)) {
+      } else if (!onlineServers.contains(regionLocation)) {
         // Region is located on a server that isn't online
         List<Pair<HRegionInfo, Result>> offlineRegions =
           offlineServers.get(regionLocation);

src/main/java/org/apache/hadoop/hbase/master/HMaster.java

@@ -26,6 +26,7 @@ import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -191,6 +192,8 @@ Server {
   private volatile boolean isActiveMaster = false;
   // flag set after we complete initialization once active (used for testing)
   private volatile boolean initialized = false;
+  // flag set after we complete assignRootAndMeta.
+  private volatile boolean serverShutdownHandlerEnabled = false;
 
   // Instance of the hbase executor service.
   ExecutorService executorService;
@@ -527,13 +530,17 @@ Server {
       }
     }
 
+    Set<ServerName> onlineServers = new HashSet<ServerName>(serverManager
+        .getOnlineServers().keySet());
     // TODO: Should do this in background rather than block master startup
     status.setStatus("Splitting logs after master startup");
-    this.fileSystemManager.
+    splitLogAfterStartup(this.fileSystemManager, onlineServers);
-      splitLogAfterStartup(this.serverManager.getOnlineServers().keySet());
 
     // Make sure root and meta assigned before proceeding.
     assignRootAndMeta(status);
+    serverShutdownHandlerEnabled = true;
+    this.serverManager.expireDeadNotExpiredServers();
+
     // Update meta with new HRI if required. i.e migrate all HRI with HTD to
     // HRI with out HTD in meta and update the status in ROOT. This must happen
     // before we assign all user regions or else the assignment will fail.
@@ -543,7 +550,7 @@ Server {
 
     // Fixup assignment manager status
     status.setStatus("Starting assignment manager");
-    this.assignmentManager.joinCluster();
+    this.assignmentManager.joinCluster(onlineServers);
 
     this.balancer.setClusterStatus(getClusterStatus());
     this.balancer.setMasterServices(this);
@@ -578,6 +585,16 @@ Server {
     }
   }
 
+  /**
+   * Override to change master's splitLogAfterStartup. Used testing
+   * @param mfs
+   * @param onlineServers
+   */
+  protected void splitLogAfterStartup(final MasterFileSystem mfs,
+      Set<ServerName> onlineServers) {
+    mfs.splitLogAfterStartup(onlineServers);
+  }
+
   /**
    * Check <code>-ROOT-</code> and <code>.META.</code> are assigned.  If not,
    * assign them.
@@ -595,17 +612,11 @@ Server {
     status.setStatus("Assigning ROOT region");
     boolean rit = this.assignmentManager.
       processRegionInTransitionAndBlockUntilAssigned(HRegionInfo.ROOT_REGIONINFO);
-    ServerName expiredServer = null;
+    ServerName currentRootServer = null;
     if (!catalogTracker.verifyRootRegionLocation(timeout)) {
-      ServerName currentRootServer = this.catalogTracker.getRootLocation();
+      currentRootServer = this.catalogTracker.getRootLocation();
-      if (expireIfOnline(currentRootServer)) {
+      splitLogAndExpireIfOnline(currentRootServer);
-        // We are expiring this server. The processing of expiration will assign
+      this.assignmentManager.assignRoot();
-        // root so don't do it here.
-        expiredServer = currentRootServer;
-      } else {
-        // Root was not on an online server when we failed verification
-        this.assignmentManager.assignRoot();
-      }
       this.catalogTracker.waitForRoot();
       //This guarantees that the transition has completed
       this.assignmentManager.waitForAssignment(HRegionInfo.ROOT_REGIONINFO);
@@ -625,13 +636,11 @@ Server {
     if (!this.catalogTracker.verifyMetaRegionLocation(timeout)) {
       ServerName currentMetaServer =
         this.catalogTracker.getMetaLocationOrReadLocationFromRoot();
-      if (currentMetaServer != null && currentMetaServer.equals(expiredServer)) {
+      if (currentMetaServer != null
-        // We are expiring the server that is carrying meta already.
+          && !currentMetaServer.equals(currentRootServer)) {
-        // The expiration processing will take care of reassigning meta.
+        splitLogAndExpireIfOnline(currentMetaServer);
-        expireIfOnline(currentMetaServer);
-      } else {
-        this.assignmentManager.assignMeta();
       }
+      assignmentManager.assignMeta();
       this.catalogTracker.waitForMeta();
       // Above check waits for general meta availability but this does not
       // guarantee that the transition has completed
@@ -682,16 +691,19 @@ Server {
   }
 
   /**
-   * Expire a server if we find it is one of the online servers set.
+   * Split a server's log and expire it if we find it is one of the online
+   * servers.
    * @param sn ServerName to check.
-   * @return True if server was online and so we expired it as unreachable.
+   * @throws IOException
    */
-  private boolean expireIfOnline(final ServerName sn) {
+  private void splitLogAndExpireIfOnline(final ServerName sn)
-    if (sn == null) return false;
+      throws IOException {
-    if (!this.serverManager.isServerOnline(sn)) return false;
+    if (sn == null || !serverManager.isServerOnline(sn)) {
-    LOG.info("Forcing expiration of " + sn);
+      return;
-    this.serverManager.expireServer(sn);
+    }
-    return true;
+    LOG.info("Forcing splitLog and expire of " + sn);
+    fileSystemManager.splitLog(sn);
+    serverManager.expireServer(sn);
   }
 
   @Override
@@ -1693,6 +1705,15 @@ Server {
     return initialized;
   }
 
+  /**
+   * ServerShutdownHandlerEnabled is set false before completing
+   * assignRootAndMeta to prevent processing of ServerShutdownHandler.
+   * @return true if assignRootAndMeta has completed;
+   */
+  public boolean isServerShutdownHandlerEnabled() {
+    return this.serverShutdownHandlerEnabled;
+  }
+
   @Override
   @Deprecated
   public void assign(final byte[] regionName, final boolean force)

src/main/java/org/apache/hadoop/hbase/master/MasterServices.java

@@ -25,8 +25,6 @@ import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hbase.HTableDescriptor;
 import org.apache.hadoop.hbase.Server;
 import org.apache.hadoop.hbase.TableDescriptors;
-import org.apache.hadoop.hbase.TableNotDisabledException;
-import org.apache.hadoop.hbase.TableNotFoundException;
 import org.apache.hadoop.hbase.executor.EventHandler;
 import org.apache.hadoop.hbase.executor.ExecutorService;
 import org.apache.hadoop.hbase.zookeeper.MasterSchemaChangeTracker;
@@ -94,4 +92,9 @@ public interface MasterServices extends Server {
    */
   public RegionServerTracker getRegionServerTracker();
 
+  /**
+   * @return true if master enables ServerShutdownHandler;
+   */
+  public boolean isServerShutdownHandlerEnabled();
+
 }

src/main/java/org/apache/hadoop/hbase/master/ServerManager.java

@@ -24,6 +24,8 @@ import java.net.InetAddress;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -46,10 +48,10 @@ import org.apache.hadoop.hbase.client.HConnection;
 import org.apache.hadoop.hbase.client.HConnectionManager;
 import org.apache.hadoop.hbase.client.RetriesExhaustedException;
 import org.apache.hadoop.hbase.ipc.HRegionInterface;
-import org.apache.hadoop.hbase.regionserver.RegionOpeningState;
 import org.apache.hadoop.hbase.master.handler.MetaServerShutdownHandler;
 import org.apache.hadoop.hbase.master.handler.ServerShutdownHandler;
 import org.apache.hadoop.hbase.monitoring.MonitoredTask;
+import org.apache.hadoop.hbase.regionserver.RegionOpeningState;
 
 /**
  * The ServerManager class manages info about region servers.
@@ -97,6 +99,14 @@ public class ServerManager {
 
   private final long maxSkew;
 
+  /**
+   * Set of region servers which are dead but not expired immediately. If one
+   * server died before master enables ServerShutdownHandler, the server will be
+   * added to set and will be expired through calling
+   * {@link ServerManager#expireDeadNotExpiredServers()} by master.
+   */
+  private Set<ServerName> deadNotExpiredServers = new HashSet<ServerName>();
+
   /**
    * Constructor.
    * @param master
@@ -349,6 +359,12 @@ public class ServerManager {
    * shutdown processing.
    */
   public synchronized void expireServer(final ServerName serverName) {
+    if (!services.isServerShutdownHandlerEnabled()) {
+      LOG.info("Master doesn't enable ServerShutdownHandler during initialization, "
+          + "delay expiring server " + serverName);
+      this.deadNotExpiredServers.add(serverName);
+      return;
+    }
     excludeRegionServerFromSchemaChanges(serverName);
     if (!this.onlineServers.containsKey(serverName)) {
       LOG.warn("Received expiration of " + serverName +
@@ -395,6 +411,22 @@ public class ServerManager {
         carryingRoot + ", meta=" + carryingMeta);
   }
 
+  /**
+   * Expire the servers which died during master's initialization. It will be
+   * called after HMaster#assignRootAndMeta.
+   * @throws IOException
+   * */
+  synchronized void expireDeadNotExpiredServers() throws IOException {
+    if (!services.isServerShutdownHandlerEnabled()) {
+      throw new IOException("Master hasn't enabled ServerShutdownHandler ");
+    }
+    Iterator<ServerName> serverIterator = deadNotExpiredServers.iterator();
+    while (serverIterator.hasNext()) {
+      expireServer(serverIterator.next());
+      serverIterator.remove();
+    }
+  }
+
   /*
    * Remove the server from the drain list.
    */
@@ -606,6 +638,13 @@ public class ServerManager {
     return new ArrayList<ServerName>(this.drainingServers);
   }
 
+  /**
+   * @return A copy of the internal set of deadNotExpired servers.
+   */
+  Set<ServerName> getDeadNotExpiredServers() {
+    return new HashSet<ServerName>(this.deadNotExpiredServers);
+  }
+
   public boolean isServerOnline(ServerName serverName) {
     return onlineServers.containsKey(serverName);
   }

src/main/java/org/apache/hadoop/hbase/master/handler/CreateTableHandler.java

@@ -172,6 +172,8 @@ public class CreateTableHandler extends EventHandler {
 
     // 4. Trigger immediate assignment of the regions in round-robin fashion
     List<ServerName> servers = serverManager.getOnlineServersList();
+    // Remove the deadNotExpired servers from the server list.
+    assignmentManager.removeDeadNotExpiredServers(servers);
     try {
       this.assignmentManager.assignUserRegions(Arrays.asList(newRegions),
         servers);

src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java

@@ -780,7 +780,7 @@ public class HRegionServer implements HRegionInterface, HBaseRPCErrorHandler,
     // Interrupt catalog tracker here in case any regions being opened out in
     // handlers are stuck waiting on meta or root.
     if (this.catalogTracker != null) this.catalogTracker.stop();
-    if (this.fsOk) {
+    if (!this.killed && this.fsOk) {
       waitOnAllRegionsToClose(abortRequested);
       LOG.info("stopping server " + this.serverNameFromMasterPOV +
         "; all regions closed.");

src/test/java/org/apache/hadoop/hbase/master/TestAssignmentManager.java

@@ -22,17 +22,22 @@ import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.hadoop.hbase.HBaseTestingUtility;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.HServerLoad;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.Server;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.SmallTests;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
 import org.apache.hadoop.hbase.catalog.CatalogTracker;
+import org.apache.hadoop.hbase.client.Get;
 import org.apache.hadoop.hbase.client.HConnection;
 import org.apache.hadoop.hbase.client.HConnectionTestingUtility;
 import org.apache.hadoop.hbase.client.Result;
@@ -45,6 +50,7 @@ import org.apache.hadoop.hbase.ipc.HRegionInterface;
 import org.apache.hadoop.hbase.master.handler.ServerShutdownHandler;
 import org.apache.hadoop.hbase.regionserver.RegionOpeningState;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.util.Writables;
 import org.apache.hadoop.hbase.zookeeper.ZKAssign;
@@ -59,10 +65,6 @@ import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 import org.mockito.Mockito;
-import org.apache.hadoop.hbase.util.Pair;
-import org.apache.hadoop.hbase.client.Get;
-import java.util.Map;
-import java.util.concurrent.atomic.AtomicBoolean;
 
 
 /**
@@ -115,10 +117,12 @@ public class TestAssignmentManager {
     this.serverManager = Mockito.mock(ServerManager.class);
     Mockito.when(this.serverManager.isServerOnline(SERVERNAME_A)).thenReturn(true);
     Mockito.when(this.serverManager.isServerOnline(SERVERNAME_B)).thenReturn(true);
-    final List<ServerName> onlineServers = new ArrayList<ServerName>();
+    final Map<ServerName, HServerLoad> onlineServers = new HashMap<ServerName, HServerLoad>();
-    onlineServers.add(SERVERNAME_B);
+    onlineServers.put(SERVERNAME_B, new HServerLoad());
-    onlineServers.add(SERVERNAME_A);
+    onlineServers.put(SERVERNAME_A, new HServerLoad());
-    Mockito.when(this.serverManager.getOnlineServersList()).thenReturn(onlineServers);
+    Mockito.when(this.serverManager.getOnlineServersList()).thenReturn(
+        new ArrayList<ServerName>(onlineServers.keySet()));
+    Mockito.when(this.serverManager.getOnlineServers()).thenReturn(onlineServers);
     Mockito.when(this.serverManager.sendRegionClose(SERVERNAME_A, REGIONINFO, -1)).
       thenReturn(true);
     Mockito.when(this.serverManager.sendRegionClose(SERVERNAME_B, REGIONINFO, -1)).

src/test/java/org/apache/hadoop/hbase/master/TestCatalogJanitor.java

@@ -35,7 +35,17 @@ import java.util.TreeMap;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hbase.*;
+import org.apache.hadoop.hbase.HBaseTestingUtility;
+import org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.NotAllMetaRegionsOnlineException;
+import org.apache.hadoop.hbase.Server;
+import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.SmallTests;
+import org.apache.hadoop.hbase.TableDescriptors;
 import org.apache.hadoop.hbase.catalog.CatalogTracker;
 import org.apache.hadoop.hbase.client.HConnection;
 import org.apache.hadoop.hbase.client.HConnectionManager;
@@ -260,6 +270,11 @@ public class TestCatalogJanitor {
     public RegionServerTracker getRegionServerTracker() {
       return null;
     }
+
+    @Override
+    public boolean isServerShutdownHandlerEnabled() {
+      return true;
+    }
   }
 
   @Test

src/test/java/org/apache/hadoop/hbase/regionserver/TestRSKilledWhenMasterInitializing.java

@@ -0,0 +1,261 @@
+/*
+ * Copyright The Apache Software Foundation
+ *
+ * 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.hbase.regionserver;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HBaseTestingUtility;
+import org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.MiniHBaseCluster;
+import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.client.HBaseAdmin;
+import org.apache.hadoop.hbase.client.HTable;
+import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.ResultScanner;
+import org.apache.hadoop.hbase.client.Scan;
+import org.apache.hadoop.hbase.master.HMaster;
+import org.apache.hadoop.hbase.master.MasterFileSystem;
+import org.apache.hadoop.hbase.master.ServerManager;
+import org.apache.hadoop.hbase.master.TestMasterFailover;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.JVMClusterUtil.MasterThread;
+import org.apache.hadoop.hbase.util.Threads;
+import org.apache.zookeeper.KeeperException;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+public class TestRSKilledWhenMasterInitializing {
+  private static final Log LOG = LogFactory.getLog(TestMasterFailover.class);
+
+  private static final HBaseTestingUtility TESTUTIL = new HBaseTestingUtility();
+  private static final int NUM_MASTERS = 1;
+  private static final int NUM_RS = 4;
+
+  @BeforeClass
+  public static void setUpBeforeClass() throws Exception {
+    // Set it so that this test runs with my custom master
+    TESTUTIL.getConfiguration().setClass(HConstants.MASTER_IMPL,
+        TestingMaster.class, HMaster.class);
+    // Start up the cluster.
+    TESTUTIL.startMiniCluster(NUM_MASTERS, NUM_RS);
+  }
+
+  @AfterClass
+  public static void tearDownAfterClass() throws Exception {
+    if (!TESTUTIL.getHBaseCluster().getMaster().isInitialized()) {
+      // master is not initialized and is waiting something forever.
+      for (MasterThread mt : TESTUTIL.getHBaseCluster().getLiveMasterThreads()) {
+        mt.interrupt();
+      }
+    }
+    TESTUTIL.shutdownMiniCluster();
+  }
+
+  /**
+   * An HMaster instance used in this test. If 'TestingMaster.sleep' is set in
+   * the Configuration, then we'll sleep after log is split and we'll also
+   * return a custom RegionServerTracker.
+   */
+  public static class TestingMaster extends HMaster {
+    private boolean logSplit = false;
+
+    public TestingMaster(Configuration conf) throws IOException,
+        KeeperException, InterruptedException {
+      super(conf);
+    }
+
+    @Override
+    protected void splitLogAfterStartup(MasterFileSystem mfs,
+        Set<ServerName> onlineServers) {
+      super.splitLogAfterStartup(mfs, onlineServers);
+      logSplit = true;
+      // If "TestingMaster.sleep" is set, sleep after log split.
+      if (getConfiguration().getBoolean("TestingMaster.sleep", false)) {
+        int duration = getConfiguration().getInt(
+            "TestingMaster.sleep.duration", 0);
+        Threads.sleep(duration);
+      }
+    }
+
+
+    public boolean isLogSplitAfterStartup() {
+      return logSplit;
+    }
+  }
+
+  @Test(timeout = 120000)
+  public void testCorrectnessWhenMasterFailOver() throws Exception {
+    final byte[] TABLENAME = Bytes.toBytes("testCorrectnessWhenMasterFailOver");
+    final byte[] FAMILY = Bytes.toBytes("family");
+    final byte[][] SPLITKEYS = { Bytes.toBytes("b"), Bytes.toBytes("i") };
+
+    MiniHBaseCluster cluster = TESTUTIL.getHBaseCluster();
+
+    HTableDescriptor desc = new HTableDescriptor(TABLENAME);
+    desc.addFamily(new HColumnDescriptor(FAMILY));
+    HBaseAdmin hbaseAdmin = TESTUTIL.getHBaseAdmin();
+    hbaseAdmin.createTable(desc, SPLITKEYS);
+
+    assertTrue(hbaseAdmin.isTableAvailable(TABLENAME));
+
+    HTable table = new HTable(TESTUTIL.getConfiguration(), TABLENAME);
+    List<Put> puts = new ArrayList<Put>();
+    Put put1 = new Put(Bytes.toBytes("a"));
+    put1.add(FAMILY, Bytes.toBytes("q1"), Bytes.toBytes("value"));
+    Put put2 = new Put(Bytes.toBytes("h"));
+    put2.add(FAMILY, Bytes.toBytes("q1"), Bytes.toBytes("value"));
+    Put put3 = new Put(Bytes.toBytes("o"));
+    put3.add(FAMILY, Bytes.toBytes("q1"), Bytes.toBytes("value"));
+    puts.add(put1);
+    puts.add(put2);
+    puts.add(put3);
+    table.put(puts);
+    ResultScanner resultScanner = table.getScanner(new Scan());
+    int count = 0;
+    while (resultScanner.next() != null) {
+      count++;
+    }
+    resultScanner.close();
+    table.close();
+    assertEquals(3, count);
+
+    /* Starting test */
+    cluster.getConfiguration().setBoolean("TestingMaster.sleep", true);
+    cluster.getConfiguration().setInt("TestingMaster.sleep.duration", 10000);
+
+    /* NO.1 .META. region correctness */
+    // First abort master
+    abortMaster(cluster);
+    TestingMaster master = startMasterAndWaitUntilLogSplit(cluster);
+
+    // Second kill meta server
+    int metaServerNum = cluster.getServerWithMeta();
+    int rootServerNum = cluster.getServerWith(HRegionInfo.ROOT_REGIONINFO
+        .getRegionName());
+    HRegionServer metaRS = cluster.getRegionServer(metaServerNum);
+    LOG.debug("Killing metaRS and carryingRoot = "
+        + (metaServerNum == rootServerNum));
+    metaRS.kill();
+    metaRS.join();
+
+    /*
+     * Sleep double time of TestingMaster.sleep.duration, so we can ensure that
+     * master has already assigned ROOTandMETA or is blocking on assigning
+     * ROOTandMETA
+     */
+    Thread.sleep(10000 * 2);
+
+    waitUntilMasterIsInitialized(master);
+
+    // Third check whether data is correct in meta region
+    assertTrue(hbaseAdmin.isTableAvailable(TABLENAME));
+
+    /*
+     * NO.2 -ROOT- region correctness . If the .META. server killed in the NO.1
+     * is also carrying -ROOT- region, it is not needed
+     */
+    if (rootServerNum != metaServerNum) {
+      // First abort master
+      abortMaster(cluster);
+      master = startMasterAndWaitUntilLogSplit(cluster);
+
+      // Second kill meta server
+      HRegionServer rootRS = cluster.getRegionServer(rootServerNum);
+      LOG.debug("Killing rootRS");
+      rootRS.kill();
+      rootRS.join();
+
+      /*
+       * Sleep double time of TestingMaster.sleep.duration, so we can ensure
+       * that master has already assigned ROOTandMETA or is blocking on
+       * assigning ROOTandMETA
+       */
+      Thread.sleep(10000 * 2);
+      waitUntilMasterIsInitialized(master);
+
+      // Third check whether data is correct in meta region
+      assertTrue(hbaseAdmin.isTableAvailable(TABLENAME));
+    }
+
+    /* NO.3 data region correctness */
+    ServerManager serverManager = cluster.getMaster().getServerManager();
+    while (serverManager.areDeadServersInProgress()) {
+      Thread.sleep(100);
+    }
+    table = new HTable(TESTUTIL.getConfiguration(), TABLENAME);
+    resultScanner = table.getScanner(new Scan());
+    count = 0;
+    while (resultScanner.next() != null) {
+      count++;
+    }
+    resultScanner.close();
+    table.close();
+    assertEquals(3, count);
+  }
+
+  private void abortMaster(MiniHBaseCluster cluster)
+      throws InterruptedException {
+    for (MasterThread mt : cluster.getLiveMasterThreads()) {
+      if (mt.getMaster().isActiveMaster()) {
+        mt.getMaster().abort("Aborting for tests", new Exception("Trace info"));
+        mt.join();
+        break;
+      }
+    }
+    LOG.debug("Master is aborted");
+  }
+
+  private TestingMaster startMasterAndWaitUntilLogSplit(MiniHBaseCluster cluster)
+      throws IOException, InterruptedException {
+    TestingMaster master = (TestingMaster) cluster.startMaster().getMaster();
+    while (!master.isLogSplitAfterStartup()) {
+      Thread.sleep(100);
+    }
+    LOG.debug("splitted:" + master.isLogSplitAfterStartup() + ",initialized:"
+        + master.isInitialized());
+    return master;
+  }
+
+  private void waitUntilMasterIsInitialized(HMaster master)
+      throws InterruptedException {
+    while (!master.isInitialized()) {
+      Thread.sleep(100);
+    }
+    LOG.debug("master isInitialized");
+  }
+  
+  @org.junit.Rule
+  public org.apache.hadoop.hbase.ResourceCheckerJUnitRule cu =
+    new org.apache.hadoop.hbase.ResourceCheckerJUnitRule();
+
+}