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HMaster.java
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HMaster.java
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/*
* 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.master;
import static org.apache.hadoop.hbase.HConstants.DEFAULT_HBASE_SPLIT_COORDINATED_BY_ZK;
import static org.apache.hadoop.hbase.HConstants.HBASE_MASTER_LOGCLEANER_PLUGINS;
import static org.apache.hadoop.hbase.HConstants.HBASE_SPLIT_WAL_COORDINATED_BY_ZK;
import static org.apache.hadoop.hbase.util.DNS.MASTER_HOSTNAME_KEY;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.ChoreService;
import org.apache.hadoop.hbase.ClusterId;
import org.apache.hadoop.hbase.ClusterMetrics;
import org.apache.hadoop.hbase.ClusterMetrics.Option;
import org.apache.hadoop.hbase.ClusterMetricsBuilder;
import org.apache.hadoop.hbase.DoNotRetryIOException;
import org.apache.hadoop.hbase.HBaseIOException;
import org.apache.hadoop.hbase.HBaseInterfaceAudience;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.InvalidFamilyOperationException;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.MetaTableAccessor;
import org.apache.hadoop.hbase.NamespaceDescriptor;
import org.apache.hadoop.hbase.PleaseHoldException;
import org.apache.hadoop.hbase.RegionMetrics;
import org.apache.hadoop.hbase.ReplicationPeerNotFoundException;
import org.apache.hadoop.hbase.ServerMetrics;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.TableNotDisabledException;
import org.apache.hadoop.hbase.TableNotFoundException;
import org.apache.hadoop.hbase.UnknownRegionException;
import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
import org.apache.hadoop.hbase.client.CompactionState;
import org.apache.hadoop.hbase.client.MasterSwitchType;
import org.apache.hadoop.hbase.client.NormalizeTableFilterParams;
import org.apache.hadoop.hbase.client.RegionInfo;
import org.apache.hadoop.hbase.client.RegionInfoBuilder;
import org.apache.hadoop.hbase.client.RegionStatesCount;
import org.apache.hadoop.hbase.client.TableDescriptor;
import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
import org.apache.hadoop.hbase.client.TableState;
import org.apache.hadoop.hbase.coprocessor.CoprocessorHost;
import org.apache.hadoop.hbase.exceptions.MasterStoppedException;
import org.apache.hadoop.hbase.executor.ExecutorType;
import org.apache.hadoop.hbase.favored.FavoredNodesManager;
import org.apache.hadoop.hbase.http.InfoServer;
import org.apache.hadoop.hbase.ipc.CoprocessorRpcUtils;
import org.apache.hadoop.hbase.ipc.RpcServer;
import org.apache.hadoop.hbase.ipc.ServerNotRunningYetException;
import org.apache.hadoop.hbase.log.HBaseMarkers;
import org.apache.hadoop.hbase.master.MasterRpcServices.BalanceSwitchMode;
import org.apache.hadoop.hbase.master.assignment.AssignmentManager;
import org.apache.hadoop.hbase.master.assignment.MergeTableRegionsProcedure;
import org.apache.hadoop.hbase.master.assignment.RegionStateNode;
import org.apache.hadoop.hbase.master.assignment.RegionStates;
import org.apache.hadoop.hbase.master.assignment.TransitRegionStateProcedure;
import org.apache.hadoop.hbase.master.balancer.BalancerChore;
import org.apache.hadoop.hbase.master.balancer.ClusterStatusChore;
import org.apache.hadoop.hbase.master.balancer.LoadBalancerFactory;
import org.apache.hadoop.hbase.master.cleaner.DirScanPool;
import org.apache.hadoop.hbase.master.cleaner.HFileCleaner;
import org.apache.hadoop.hbase.master.cleaner.LogCleaner;
import org.apache.hadoop.hbase.master.cleaner.ReplicationBarrierCleaner;
import org.apache.hadoop.hbase.master.cleaner.SnapshotCleanerChore;
import org.apache.hadoop.hbase.master.janitor.CatalogJanitor;
import org.apache.hadoop.hbase.master.locking.LockManager;
import org.apache.hadoop.hbase.master.normalizer.RegionNormalizerFactory;
import org.apache.hadoop.hbase.master.normalizer.RegionNormalizerManager;
import org.apache.hadoop.hbase.master.procedure.CreateTableProcedure;
import org.apache.hadoop.hbase.master.procedure.DeleteNamespaceProcedure;
import org.apache.hadoop.hbase.master.procedure.DeleteTableProcedure;
import org.apache.hadoop.hbase.master.procedure.DisableTableProcedure;
import org.apache.hadoop.hbase.master.procedure.EnableTableProcedure;
import org.apache.hadoop.hbase.master.procedure.InitMetaProcedure;
import org.apache.hadoop.hbase.master.procedure.MasterProcedureConstants;
import org.apache.hadoop.hbase.master.procedure.MasterProcedureEnv;
import org.apache.hadoop.hbase.master.procedure.MasterProcedureScheduler;
import org.apache.hadoop.hbase.master.procedure.MasterProcedureUtil;
import org.apache.hadoop.hbase.master.procedure.MasterProcedureUtil.NonceProcedureRunnable;
import org.apache.hadoop.hbase.master.procedure.ModifyTableProcedure;
import org.apache.hadoop.hbase.master.procedure.ProcedurePrepareLatch;
import org.apache.hadoop.hbase.master.procedure.ProcedureSyncWait;
import org.apache.hadoop.hbase.master.procedure.ReopenTableRegionsProcedure;
import org.apache.hadoop.hbase.master.procedure.ServerCrashProcedure;
import org.apache.hadoop.hbase.master.procedure.TruncateTableProcedure;
import org.apache.hadoop.hbase.master.region.MasterRegion;
import org.apache.hadoop.hbase.master.region.MasterRegionFactory;
import org.apache.hadoop.hbase.master.replication.AbstractPeerProcedure;
import org.apache.hadoop.hbase.master.replication.AddPeerProcedure;
import org.apache.hadoop.hbase.master.replication.DisablePeerProcedure;
import org.apache.hadoop.hbase.master.replication.EnablePeerProcedure;
import org.apache.hadoop.hbase.master.replication.RemovePeerProcedure;
import org.apache.hadoop.hbase.master.replication.ReplicationPeerManager;
import org.apache.hadoop.hbase.master.replication.SyncReplicationReplayWALManager;
import org.apache.hadoop.hbase.master.replication.TransitPeerSyncReplicationStateProcedure;
import org.apache.hadoop.hbase.master.replication.UpdatePeerConfigProcedure;
import org.apache.hadoop.hbase.master.slowlog.SlowLogMasterService;
import org.apache.hadoop.hbase.master.snapshot.SnapshotManager;
import org.apache.hadoop.hbase.master.zksyncer.MasterAddressSyncer;
import org.apache.hadoop.hbase.master.zksyncer.MetaLocationSyncer;
import org.apache.hadoop.hbase.mob.MobFileCleanerChore;
import org.apache.hadoop.hbase.mob.MobFileCompactionChore;
import org.apache.hadoop.hbase.monitoring.MemoryBoundedLogMessageBuffer;
import org.apache.hadoop.hbase.monitoring.MonitoredTask;
import org.apache.hadoop.hbase.monitoring.TaskMonitor;
import org.apache.hadoop.hbase.procedure.MasterProcedureManagerHost;
import org.apache.hadoop.hbase.procedure.flush.MasterFlushTableProcedureManager;
import org.apache.hadoop.hbase.procedure2.LockedResource;
import org.apache.hadoop.hbase.procedure2.Procedure;
import org.apache.hadoop.hbase.procedure2.ProcedureEvent;
import org.apache.hadoop.hbase.procedure2.ProcedureExecutor;
import org.apache.hadoop.hbase.procedure2.RemoteProcedureDispatcher.RemoteProcedure;
import org.apache.hadoop.hbase.procedure2.RemoteProcedureException;
import org.apache.hadoop.hbase.procedure2.store.ProcedureStore;
import org.apache.hadoop.hbase.procedure2.store.ProcedureStore.ProcedureStoreListener;
import org.apache.hadoop.hbase.procedure2.store.region.RegionProcedureStore;
import org.apache.hadoop.hbase.quotas.MasterQuotaManager;
import org.apache.hadoop.hbase.quotas.MasterQuotasObserver;
import org.apache.hadoop.hbase.quotas.QuotaObserverChore;
import org.apache.hadoop.hbase.quotas.QuotaTableUtil;
import org.apache.hadoop.hbase.quotas.QuotaUtil;
import org.apache.hadoop.hbase.quotas.SnapshotQuotaObserverChore;
import org.apache.hadoop.hbase.quotas.SpaceQuotaSnapshot;
import org.apache.hadoop.hbase.quotas.SpaceQuotaSnapshot.SpaceQuotaStatus;
import org.apache.hadoop.hbase.quotas.SpaceQuotaSnapshotNotifier;
import org.apache.hadoop.hbase.quotas.SpaceQuotaSnapshotNotifierFactory;
import org.apache.hadoop.hbase.quotas.SpaceViolationPolicy;
import org.apache.hadoop.hbase.regionserver.HRegionServer;
import org.apache.hadoop.hbase.regionserver.RSRpcServices;
import org.apache.hadoop.hbase.replication.ReplicationException;
import org.apache.hadoop.hbase.replication.ReplicationLoadSource;
import org.apache.hadoop.hbase.replication.ReplicationPeerConfig;
import org.apache.hadoop.hbase.replication.ReplicationPeerDescription;
import org.apache.hadoop.hbase.replication.ReplicationUtils;
import org.apache.hadoop.hbase.replication.SyncReplicationState;
import org.apache.hadoop.hbase.replication.master.ReplicationHFileCleaner;
import org.apache.hadoop.hbase.replication.master.ReplicationLogCleaner;
import org.apache.hadoop.hbase.replication.regionserver.ReplicationStatus;
import org.apache.hadoop.hbase.rsgroup.RSGroupAdminEndpoint;
import org.apache.hadoop.hbase.rsgroup.RSGroupBasedLoadBalancer;
import org.apache.hadoop.hbase.rsgroup.RSGroupInfoManager;
import org.apache.hadoop.hbase.rsgroup.RSGroupUtil;
import org.apache.hadoop.hbase.security.AccessDeniedException;
import org.apache.hadoop.hbase.security.SecurityConstants;
import org.apache.hadoop.hbase.security.UserProvider;
import org.apache.hadoop.hbase.trace.TraceUtil;
import org.apache.hadoop.hbase.util.Addressing;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.FutureUtils;
import org.apache.hadoop.hbase.util.HBaseFsck;
import org.apache.hadoop.hbase.util.HFileArchiveUtil;
import org.apache.hadoop.hbase.util.IdLock;
import org.apache.hadoop.hbase.util.ModifyRegionUtils;
import org.apache.hadoop.hbase.util.Pair;
import org.apache.hadoop.hbase.util.RetryCounter;
import org.apache.hadoop.hbase.util.RetryCounterFactory;
import org.apache.hadoop.hbase.util.TableDescriptorChecker;
import org.apache.hadoop.hbase.util.Threads;
import org.apache.hadoop.hbase.util.VersionInfo;
import org.apache.hadoop.hbase.zookeeper.LoadBalancerTracker;
import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
import org.apache.hadoop.hbase.zookeeper.RegionNormalizerTracker;
import org.apache.hadoop.hbase.zookeeper.SnapshotCleanupTracker;
import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
import org.apache.hadoop.hbase.zookeeper.ZKUtil;
import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
import org.apache.yetus.audience.InterfaceAudience;
import org.apache.zookeeper.KeeperException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hbase.thirdparty.com.google.common.annotations.VisibleForTesting;
import org.apache.hbase.thirdparty.com.google.common.collect.Lists;
import org.apache.hbase.thirdparty.com.google.common.collect.Maps;
import org.apache.hbase.thirdparty.com.google.common.collect.Sets;
import org.apache.hbase.thirdparty.com.google.protobuf.Descriptors;
import org.apache.hbase.thirdparty.com.google.protobuf.Service;
import org.apache.hbase.thirdparty.org.eclipse.jetty.server.Server;
import org.apache.hbase.thirdparty.org.eclipse.jetty.server.ServerConnector;
import org.apache.hbase.thirdparty.org.eclipse.jetty.servlet.ServletHolder;
import org.apache.hbase.thirdparty.org.eclipse.jetty.webapp.WebAppContext;
import org.apache.hadoop.hbase.shaded.protobuf.RequestConverter;
import org.apache.hadoop.hbase.shaded.protobuf.generated.AdminProtos.GetRegionInfoResponse;
import org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription;
/**
* HMaster is the "master server" for HBase. An HBase cluster has one active
* master. If many masters are started, all compete. Whichever wins goes on to
* run the cluster. All others park themselves in their constructor until
* master or cluster shutdown or until the active master loses its lease in
* zookeeper. Thereafter, all running master jostle to take over master role.
*
* <p>The Master can be asked shutdown the cluster. See {@link #shutdown()}. In
* this case it will tell all regionservers to go down and then wait on them
* all reporting in that they are down. This master will then shut itself down.
*
* <p>You can also shutdown just this master. Call {@link #stopMaster()}.
*
* @see org.apache.zookeeper.Watcher
*/
@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.TOOLS)
@SuppressWarnings("deprecation")
public class HMaster extends HRegionServer implements MasterServices {
private static Logger LOG = LoggerFactory.getLogger(HMaster.class);
/**
* Protection against zombie master. Started once Master accepts active responsibility and
* starts taking over responsibilities. Allows a finite time window before giving up ownership.
*/
private static class InitializationMonitor extends Thread {
/** The amount of time in milliseconds to sleep before checking initialization status. */
public static final String TIMEOUT_KEY = "hbase.master.initializationmonitor.timeout";
public static final long TIMEOUT_DEFAULT = TimeUnit.MILLISECONDS.convert(15, TimeUnit.MINUTES);
/**
* When timeout expired and initialization has not complete, call {@link System#exit(int)} when
* true, do nothing otherwise.
*/
public static final String HALT_KEY = "hbase.master.initializationmonitor.haltontimeout";
public static final boolean HALT_DEFAULT = false;
private final HMaster master;
private final long timeout;
private final boolean haltOnTimeout;
/** Creates a Thread that monitors the {@link #isInitialized()} state. */
InitializationMonitor(HMaster master) {
super("MasterInitializationMonitor");
this.master = master;
this.timeout = master.getConfiguration().getLong(TIMEOUT_KEY, TIMEOUT_DEFAULT);
this.haltOnTimeout = master.getConfiguration().getBoolean(HALT_KEY, HALT_DEFAULT);
this.setDaemon(true);
}
@Override
public void run() {
try {
while (!master.isStopped() && master.isActiveMaster()) {
Thread.sleep(timeout);
if (master.isInitialized()) {
LOG.debug("Initialization completed within allotted tolerance. Monitor exiting.");
} else {
LOG.error("Master failed to complete initialization after " + timeout + "ms. Please"
+ " consider submitting a bug report including a thread dump of this process.");
if (haltOnTimeout) {
LOG.error("Zombie Master exiting. Thread dump to stdout");
Threads.printThreadInfo(System.out, "Zombie HMaster");
System.exit(-1);
}
}
}
} catch (InterruptedException ie) {
LOG.trace("InitMonitor thread interrupted. Existing.");
}
}
}
// MASTER is name of the webapp and the attribute name used stuffing this
//instance into web context.
public static final String MASTER = "master";
// Manager and zk listener for master election
private final ActiveMasterManager activeMasterManager;
// Region server tracker
private RegionServerTracker regionServerTracker;
// Draining region server tracker
private DrainingServerTracker drainingServerTracker;
// Tracker for load balancer state
LoadBalancerTracker loadBalancerTracker;
// Tracker for meta location, if any client ZK quorum specified
MetaLocationSyncer metaLocationSyncer;
// Tracker for active master location, if any client ZK quorum specified
MasterAddressSyncer masterAddressSyncer;
// Tracker for auto snapshot cleanup state
SnapshotCleanupTracker snapshotCleanupTracker;
// Tracker for split and merge state
private SplitOrMergeTracker splitOrMergeTracker;
private ClusterSchemaService clusterSchemaService;
public static final String HBASE_MASTER_WAIT_ON_SERVICE_IN_SECONDS =
"hbase.master.wait.on.service.seconds";
public static final int DEFAULT_HBASE_MASTER_WAIT_ON_SERVICE_IN_SECONDS = 5 * 60;
public static final String HBASE_MASTER_CLEANER_INTERVAL = "hbase.master.cleaner.interval";
public static final int DEFAULT_HBASE_MASTER_CLEANER_INTERVAL = 600 * 1000;
// Metrics for the HMaster
final MetricsMaster metricsMaster;
// file system manager for the master FS operations
private MasterFileSystem fileSystemManager;
private MasterWalManager walManager;
// manager to manage procedure-based WAL splitting, can be null if current
// is zk-based WAL splitting. SplitWALManager will replace SplitLogManager
// and MasterWalManager, which means zk-based WAL splitting code will be
// useless after we switch to the procedure-based one. our eventual goal
// is to remove all the zk-based WAL splitting code.
private SplitWALManager splitWALManager;
// server manager to deal with region server info
private volatile ServerManager serverManager;
// manager of assignment nodes in zookeeper
private AssignmentManager assignmentManager;
/**
* Cache for the meta region replica's locations. Also tracks their changes to avoid stale
* cache entries.
*/
private final MetaRegionLocationCache metaRegionLocationCache;
private RSGroupInfoManager rsGroupInfoManager;
// manager of replication
private ReplicationPeerManager replicationPeerManager;
private SyncReplicationReplayWALManager syncReplicationReplayWALManager;
// buffer for "fatal error" notices from region servers
// in the cluster. This is only used for assisting
// operations/debugging.
MemoryBoundedLogMessageBuffer rsFatals;
// flag set after we become the active master (used for testing)
private volatile boolean activeMaster = false;
// flag set after we complete initialization once active
private final ProcedureEvent<?> initialized = new ProcedureEvent<>("master initialized");
// flag set after master services are started,
// initialization may have not completed yet.
volatile boolean serviceStarted = false;
// Maximum time we should run balancer for
private final int maxBalancingTime;
// Maximum percent of regions in transition when balancing
private final double maxRitPercent;
private final LockManager lockManager = new LockManager(this);
private RSGroupBasedLoadBalancer balancer;
private BalancerChore balancerChore;
private RegionNormalizerManager regionNormalizerManager;
private ClusterStatusChore clusterStatusChore;
private ClusterStatusPublisher clusterStatusPublisherChore = null;
private SnapshotCleanerChore snapshotCleanerChore = null;
private HbckChore hbckChore;
CatalogJanitor catalogJanitorChore;
private DirScanPool cleanerPool;
private LogCleaner logCleaner;
private HFileCleaner hfileCleaner;
private ReplicationBarrierCleaner replicationBarrierCleaner;
private MobFileCleanerChore mobFileCleanerChore;
private MobFileCompactionChore mobFileCompactionChore;
// used to synchronize the mobCompactionStates
private final IdLock mobCompactionLock = new IdLock();
// save the information of mob compactions in tables.
// the key is table name, the value is the number of compactions in that table.
private Map<TableName, AtomicInteger> mobCompactionStates = Maps.newConcurrentMap();
MasterCoprocessorHost cpHost;
private final boolean preLoadTableDescriptors;
// Time stamps for when a hmaster became active
private long masterActiveTime;
// Time stamp for when HMaster finishes becoming Active Master
private long masterFinishedInitializationTime;
Map<String, Service> coprocessorServiceHandlers = Maps.newHashMap();
// monitor for snapshot of hbase tables
SnapshotManager snapshotManager;
// monitor for distributed procedures
private MasterProcedureManagerHost mpmHost;
private RegionsRecoveryChore regionsRecoveryChore = null;
private RegionsRecoveryConfigManager regionsRecoveryConfigManager = null;
// it is assigned after 'initialized' guard set to true, so should be volatile
private volatile MasterQuotaManager quotaManager;
private SpaceQuotaSnapshotNotifier spaceQuotaSnapshotNotifier;
private QuotaObserverChore quotaObserverChore;
private SnapshotQuotaObserverChore snapshotQuotaChore;
private ProcedureExecutor<MasterProcedureEnv> procedureExecutor;
private ProcedureStore procedureStore;
// the master local storage to store procedure data, etc.
private MasterRegion masterRegion;
// handle table states
private TableStateManager tableStateManager;
/** jetty server for master to redirect requests to regionserver infoServer */
private Server masterJettyServer;
// Determine if we should do normal startup or minimal "single-user" mode with no region
// servers and no user tables. Useful for repair and recovery of hbase:meta
private final boolean maintenanceMode;
static final String MAINTENANCE_MODE = "hbase.master.maintenance_mode";
// Cached clusterId on stand by masters to serve clusterID requests from clients.
private final CachedClusterId cachedClusterId;
public static class RedirectServlet extends HttpServlet {
private static final long serialVersionUID = 2894774810058302473L;
private final int regionServerInfoPort;
private final String regionServerHostname;
/**
* @param infoServer that we're trying to send all requests to
* @param hostname may be null. if given, will be used for redirects instead of host from client.
*/
public RedirectServlet(InfoServer infoServer, String hostname) {
regionServerInfoPort = infoServer.getPort();
regionServerHostname = hostname;
}
@Override
public void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String redirectHost = regionServerHostname;
if(redirectHost == null) {
redirectHost = request.getServerName();
if(!Addressing.isLocalAddress(InetAddress.getByName(redirectHost))) {
LOG.warn("Couldn't resolve '" + redirectHost + "' as an address local to this node and '" +
MASTER_HOSTNAME_KEY + "' is not set; client will get an HTTP 400 response. If " +
"your HBase deployment relies on client accessible names that the region server process " +
"can't resolve locally, then you should set the previously mentioned configuration variable " +
"to an appropriate hostname.");
// no sending client provided input back to the client, so the goal host is just in the logs.
response.sendError(400, "Request was to a host that I can't resolve for any of the network interfaces on " +
"this node. If this is due to an intermediary such as an HTTP load balancer or other proxy, your HBase " +
"administrator can set '" + MASTER_HOSTNAME_KEY + "' to point to the correct hostname.");
return;
}
}
// TODO this scheme should come from looking at the scheme registered in the infoserver's http server for the
// host and port we're using, but it's buried way too deep to do that ATM.
String redirectUrl = request.getScheme() + "://"
+ redirectHost + ":" + regionServerInfoPort
+ request.getRequestURI();
response.sendRedirect(redirectUrl);
}
}
/**
* Initializes the HMaster. The steps are as follows:
* <p>
* <ol>
* <li>Initialize the local HRegionServer
* <li>Start the ActiveMasterManager.
* </ol>
* <p>
* Remaining steps of initialization occur in
* {@link #finishActiveMasterInitialization(MonitoredTask)} after the master becomes the
* active one.
*/
public HMaster(final Configuration conf) throws IOException {
super(conf);
TraceUtil.initTracer(conf);
try {
if (conf.getBoolean(MAINTENANCE_MODE, false)) {
LOG.info("Detected {}=true via configuration.", MAINTENANCE_MODE);
maintenanceMode = true;
} else if (Boolean.getBoolean(MAINTENANCE_MODE)) {
LOG.info("Detected {}=true via environment variables.", MAINTENANCE_MODE);
maintenanceMode = true;
} else {
maintenanceMode = false;
}
this.rsFatals = new MemoryBoundedLogMessageBuffer(
conf.getLong("hbase.master.buffer.for.rs.fatals", 1 * 1024 * 1024));
LOG.info("hbase.rootdir={}, hbase.cluster.distributed={}", getDataRootDir(),
this.conf.getBoolean(HConstants.CLUSTER_DISTRIBUTED, false));
// Disable usage of meta replicas in the master
this.conf.setBoolean(HConstants.USE_META_REPLICAS, false);
decorateMasterConfiguration(this.conf);
// Hack! Maps DFSClient => Master for logs. HDFS made this
// config param for task trackers, but we can piggyback off of it.
if (this.conf.get("mapreduce.task.attempt.id") == null) {
this.conf.set("mapreduce.task.attempt.id", "hb_m_" + this.serverName.toString());
}
this.metricsMaster = new MetricsMaster(new MetricsMasterWrapperImpl(this));
// preload table descriptor at startup
this.preLoadTableDescriptors = conf.getBoolean("hbase.master.preload.tabledescriptors", true);
this.maxBalancingTime = getMaxBalancingTime();
this.maxRitPercent = conf.getDouble(HConstants.HBASE_MASTER_BALANCER_MAX_RIT_PERCENT,
HConstants.DEFAULT_HBASE_MASTER_BALANCER_MAX_RIT_PERCENT);
// Do we publish the status?
boolean shouldPublish = conf.getBoolean(HConstants.STATUS_PUBLISHED,
HConstants.STATUS_PUBLISHED_DEFAULT);
Class<? extends ClusterStatusPublisher.Publisher> publisherClass =
conf.getClass(ClusterStatusPublisher.STATUS_PUBLISHER_CLASS,
ClusterStatusPublisher.DEFAULT_STATUS_PUBLISHER_CLASS,
ClusterStatusPublisher.Publisher.class);
if (shouldPublish) {
if (publisherClass == null) {
LOG.warn(HConstants.STATUS_PUBLISHED + " is true, but " +
ClusterStatusPublisher.DEFAULT_STATUS_PUBLISHER_CLASS +
" is not set - not publishing status");
} else {
clusterStatusPublisherChore = new ClusterStatusPublisher(this, conf, publisherClass);
LOG.debug("Created {}", this.clusterStatusPublisherChore);
getChoreService().scheduleChore(clusterStatusPublisherChore);
}
}
this.metaRegionLocationCache = new MetaRegionLocationCache(this.zooKeeper);
this.activeMasterManager = createActiveMasterManager(zooKeeper, serverName, this);
cachedClusterId = new CachedClusterId(this, conf);
} catch (Throwable t) {
// Make sure we log the exception. HMaster is often started via reflection and the
// cause of failed startup is lost.
LOG.error("Failed construction of Master", t);
throw t;
}
}
/**
* Protected to have custom implementations in tests override the default ActiveMaster
* implementation.
*/
protected ActiveMasterManager createActiveMasterManager(ZKWatcher zk, ServerName sn,
org.apache.hadoop.hbase.Server server) throws InterruptedIOException {
return new ActiveMasterManager(zk, sn, server);
}
@Override
protected String getUseThisHostnameInstead(Configuration conf) {
return conf.get(MASTER_HOSTNAME_KEY);
}
// Main run loop. Calls through to the regionserver run loop AFTER becoming active Master; will
// block in here until then.
@Override
public void run() {
try {
Threads.setDaemonThreadRunning(new Thread(() -> {
try {
int infoPort = putUpJettyServer();
startActiveMasterManager(infoPort);
} catch (Throwable t) {
// Make sure we log the exception.
String error = "Failed to become Active Master";
LOG.error(error, t);
// Abort should have been called already.
if (!isAborted()) {
abort(error, t);
}
}
}), getName() + ":becomeActiveMaster");
// Fall in here even if we have been aborted. Need to run the shutdown services and
// the super run call will do this for us.
super.run();
} finally {
if (this.clusterSchemaService != null) {
// If on way out, then we are no longer active master.
this.clusterSchemaService.stopAsync();
try {
this.clusterSchemaService.awaitTerminated(
getConfiguration().getInt(HBASE_MASTER_WAIT_ON_SERVICE_IN_SECONDS,
DEFAULT_HBASE_MASTER_WAIT_ON_SERVICE_IN_SECONDS), TimeUnit.SECONDS);
} catch (TimeoutException te) {
LOG.warn("Failed shutdown of clusterSchemaService", te);
}
}
this.activeMaster = false;
}
}
// return the actual infoPort, -1 means disable info server.
private int putUpJettyServer() throws IOException {
if (!conf.getBoolean("hbase.master.infoserver.redirect", true)) {
return -1;
}
final int infoPort = conf.getInt("hbase.master.info.port.orig",
HConstants.DEFAULT_MASTER_INFOPORT);
// -1 is for disabling info server, so no redirecting
if (infoPort < 0 || infoServer == null) {
return -1;
}
if(infoPort == infoServer.getPort()) {
return infoPort;
}
final String addr = conf.get("hbase.master.info.bindAddress", "0.0.0.0");
if (!Addressing.isLocalAddress(InetAddress.getByName(addr))) {
String msg =
"Failed to start redirecting jetty server. Address " + addr
+ " does not belong to this host. Correct configuration parameter: "
+ "hbase.master.info.bindAddress";
LOG.error(msg);
throw new IOException(msg);
}
// TODO I'm pretty sure we could just add another binding to the InfoServer run by
// the RegionServer and have it run the RedirectServlet instead of standing up
// a second entire stack here.
masterJettyServer = new Server();
final ServerConnector connector = new ServerConnector(masterJettyServer);
connector.setHost(addr);
connector.setPort(infoPort);
masterJettyServer.addConnector(connector);
masterJettyServer.setStopAtShutdown(true);
final String redirectHostname =
StringUtils.isBlank(useThisHostnameInstead) ? null : useThisHostnameInstead;
final RedirectServlet redirect = new RedirectServlet(infoServer, redirectHostname);
final WebAppContext context = new WebAppContext(null, "/", null, null, null, null, WebAppContext.NO_SESSIONS);
context.addServlet(new ServletHolder(redirect), "/*");
context.setServer(masterJettyServer);
try {
masterJettyServer.start();
} catch (Exception e) {
throw new IOException("Failed to start redirecting jetty server", e);
}
return connector.getLocalPort();
}
/**
* For compatibility, if failed with regionserver credentials, try the master one
*/
@Override
protected void login(UserProvider user, String host) throws IOException {
try {
super.login(user, host);
} catch (IOException ie) {
user.login(SecurityConstants.MASTER_KRB_KEYTAB_FILE,
SecurityConstants.MASTER_KRB_PRINCIPAL, host);
}
}
/**
* If configured to put regions on active master,
* wait till a backup master becomes active.
* Otherwise, loop till the server is stopped or aborted.
*/
@Override
protected void waitForMasterActive(){
if (maintenanceMode) {
return;
}
boolean tablesOnMaster = LoadBalancer.isTablesOnMaster(conf);
while (!(tablesOnMaster && activeMaster) && !isStopped() && !isAborted()) {
sleeper.sleep();
}
}
@VisibleForTesting
public MasterRpcServices getMasterRpcServices() {
return (MasterRpcServices)rpcServices;
}
public boolean balanceSwitch(final boolean b) throws IOException {
return getMasterRpcServices().switchBalancer(b, BalanceSwitchMode.ASYNC);
}
@Override
protected String getProcessName() {
return MASTER;
}
@Override
protected boolean canCreateBaseZNode() {
return true;
}
@Override
protected boolean canUpdateTableDescriptor() {
return true;
}
@Override
protected boolean cacheTableDescriptor() {
return true;
}
@Override
protected RSRpcServices createRpcServices() throws IOException {
return new MasterRpcServices(this);
}
@Override
protected void configureInfoServer() {
infoServer.addUnprivilegedServlet("master-status", "/master-status", MasterStatusServlet.class);
infoServer.setAttribute(MASTER, this);
if (LoadBalancer.isTablesOnMaster(conf)) {
super.configureInfoServer();
}
}
@Override
protected Class<? extends HttpServlet> getDumpServlet() {
return MasterDumpServlet.class;
}
@Override
public MetricsMaster getMasterMetrics() {
return metricsMaster;
}
/**
* Initialize all ZK based system trackers. But do not include {@link RegionServerTracker}, it
* should have already been initialized along with {@link ServerManager}.
*/
private void initializeZKBasedSystemTrackers()
throws IOException, KeeperException, ReplicationException {
this.balancer = new RSGroupBasedLoadBalancer();
this.balancer.setConf(conf);
this.loadBalancerTracker = new LoadBalancerTracker(zooKeeper, this);
this.loadBalancerTracker.start();
this.regionNormalizerManager =
RegionNormalizerFactory.createNormalizerManager(conf, zooKeeper, this);
this.configurationManager.registerObserver(regionNormalizerManager);
this.regionNormalizerManager.start();
this.splitOrMergeTracker = new SplitOrMergeTracker(zooKeeper, conf, this);
this.splitOrMergeTracker.start();
// This is for backwards compatible. We do not need the CP for rs group now but if user want to
// load it, we need to enable rs group.
String[] cpClasses = conf.getStrings(MasterCoprocessorHost.MASTER_COPROCESSOR_CONF_KEY);
if (cpClasses != null) {
for (String cpClass : cpClasses) {
if (RSGroupAdminEndpoint.class.getName().equals(cpClass)) {
RSGroupUtil.enableRSGroup(conf);
break;
}
}
}
this.rsGroupInfoManager = RSGroupInfoManager.create(this);
this.replicationPeerManager = ReplicationPeerManager.create(zooKeeper, conf, clusterId);
this.drainingServerTracker = new DrainingServerTracker(zooKeeper, this, this.serverManager);
this.drainingServerTracker.start();
this.snapshotCleanupTracker = new SnapshotCleanupTracker(zooKeeper, this);
this.snapshotCleanupTracker.start();
String clientQuorumServers = conf.get(HConstants.CLIENT_ZOOKEEPER_QUORUM);
boolean clientZkObserverMode = conf.getBoolean(HConstants.CLIENT_ZOOKEEPER_OBSERVER_MODE,
HConstants.DEFAULT_CLIENT_ZOOKEEPER_OBSERVER_MODE);
if (clientQuorumServers != null && !clientZkObserverMode) {
// we need to take care of the ZK information synchronization
// if given client ZK are not observer nodes
ZKWatcher clientZkWatcher = new ZKWatcher(conf,
getProcessName() + ":" + rpcServices.getSocketAddress().getPort() + "-clientZK", this,
false, true);
this.metaLocationSyncer = new MetaLocationSyncer(zooKeeper, clientZkWatcher, this);
this.metaLocationSyncer.start();
this.masterAddressSyncer = new MasterAddressSyncer(zooKeeper, clientZkWatcher, this);
this.masterAddressSyncer.start();
// set cluster id is a one-go effort
ZKClusterId.setClusterId(clientZkWatcher, fileSystemManager.getClusterId());
}
// Set the cluster as up. If new RSs, they'll be waiting on this before
// going ahead with their startup.
boolean wasUp = this.clusterStatusTracker.isClusterUp();
if (!wasUp) this.clusterStatusTracker.setClusterUp();
LOG.info("Active/primary master=" + this.serverName +
", sessionid=0x" +
Long.toHexString(this.zooKeeper.getRecoverableZooKeeper().getSessionId()) +
", setting cluster-up flag (Was=" + wasUp + ")");
// create/initialize the snapshot manager and other procedure managers
this.snapshotManager = new SnapshotManager();
this.mpmHost = new MasterProcedureManagerHost();
this.mpmHost.register(this.snapshotManager);
this.mpmHost.register(new MasterFlushTableProcedureManager());
this.mpmHost.loadProcedures(conf);
this.mpmHost.initialize(this, this.metricsMaster);
}
// Will be overriden in test to inject customized AssignmentManager
@VisibleForTesting
protected AssignmentManager createAssignmentManager(MasterServices master) {
return new AssignmentManager(master);
}
/**
* Finish initialization of HMaster after becoming the primary master.
* <p/>
* The startup order is a bit complicated but very important, do not change it unless you know
* what you are doing.
* <ol>
* <li>Initialize file system based components - file system manager, wal manager, table
* descriptors, etc</li>
* <li>Publish cluster id</li>
* <li>Here comes the most complicated part - initialize server manager, assignment manager and
* region server tracker
* <ol type='i'>
* <li>Create server manager</li>
* <li>Create procedure executor, load the procedures, but do not start workers. We will start it
* later after we finish scheduling SCPs to avoid scheduling duplicated SCPs for the same
* server</li>
* <li>Create assignment manager and start it, load the meta region state, but do not load data
* from meta region</li>
* <li>Start region server tracker, construct the online servers set and find out dead servers and
* schedule SCP for them. The online servers will be constructed by scanning zk, and we will also
* scan the wal directory to find out possible live region servers, and the differences between
* these two sets are the dead servers</li>
* </ol>
* </li>
* <li>If this is a new deploy, schedule a InitMetaProcedure to initialize meta</li>
* <li>Start necessary service threads - balancer, catalog janitor, executor services, and also
* the procedure executor, etc. Notice that the balancer must be created first as assignment
* manager may use it when assigning regions.</li>
* <li>Wait for meta to be initialized if necessary, start table state manager.</li>
* <li>Wait for enough region servers to check-in</li>
* <li>Let assignment manager load data from meta and construct region states</li>
* <li>Start all other things such as chore services, etc</li>
* </ol>
* <p/>
* Notice that now we will not schedule a special procedure to make meta online(unless the first
* time where meta has not been created yet), we will rely on SCP to bring meta online.
*/
private void finishActiveMasterInitialization(MonitoredTask status) throws IOException,
InterruptedException, KeeperException, ReplicationException {
/*
* We are active master now... go initialize components we need to run.
*/
status.setStatus("Initializing Master file system");
this.masterActiveTime = System.currentTimeMillis();
// TODO: Do this using Dependency Injection, using PicoContainer, Guice or Spring.
// always initialize the MemStoreLAB as we use a region to store data in master now, see
// localStore.
initializeMemStoreChunkCreator();
this.fileSystemManager = new MasterFileSystem(conf);
this.walManager = new MasterWalManager(this);
// warm-up HTDs cache on master initialization
if (preLoadTableDescriptors) {
status.setStatus("Pre-loading table descriptors");
this.tableDescriptors.getAll();
}
// Publish cluster ID; set it in Master too. The superclass RegionServer does this later but
// only after it has checked in with the Master. At least a few tests ask Master for clusterId
// before it has called its run method and before RegionServer has done the reportForDuty.
ClusterId clusterId = fileSystemManager.getClusterId();
status.setStatus("Publishing Cluster ID " + clusterId + " in ZooKeeper");
ZKClusterId.setClusterId(this.zooKeeper, fileSystemManager.getClusterId());
this.clusterId = clusterId.toString();
// Precaution. Put in place the old hbck1 lock file to fence out old hbase1s running their
// hbck1s against an hbase2 cluster; it could do damage. To skip this behavior, set
// hbase.write.hbck1.lock.file to false.
if (this.conf.getBoolean("hbase.write.hbck1.lock.file", true)) {
Pair<Path, FSDataOutputStream> result = null;
try {
result = HBaseFsck.checkAndMarkRunningHbck(this.conf,
HBaseFsck.createLockRetryCounterFactory(this.conf).create());
} finally {
if (result != null) {
IOUtils.closeQuietly(result.getSecond());
}
}
}
status.setStatus("Initialize ServerManager and schedule SCP for crash servers");
// The below two managers must be created before loading procedures, as they will be used during
// loading.
this.serverManager = createServerManager(this);
this.syncReplicationReplayWALManager = new SyncReplicationReplayWALManager(this);
if (!conf.getBoolean(HBASE_SPLIT_WAL_COORDINATED_BY_ZK,
DEFAULT_HBASE_SPLIT_COORDINATED_BY_ZK)) {
this.splitWALManager = new SplitWALManager(this);
}
// initialize master local region
masterRegion = MasterRegionFactory.create(this);
createProcedureExecutor();
Map<Class<?>, List<Procedure<MasterProcedureEnv>>> procsByType =
procedureExecutor.getActiveProceduresNoCopy().stream()
.collect(Collectors.groupingBy(p -> p.getClass()));
// Create Assignment Manager
this.assignmentManager = createAssignmentManager(this);
this.assignmentManager.start();
// TODO: TRSP can perform as the sub procedure for other procedures, so even if it is marked as
// completed, it could still be in the procedure list. This is a bit strange but is another
// story, need to verify the implementation for ProcedureExecutor and ProcedureStore.
List<TransitRegionStateProcedure> ritList =
procsByType.getOrDefault(TransitRegionStateProcedure.class, Collections.emptyList()).stream()
.filter(p -> !p.isFinished()).map(p -> (TransitRegionStateProcedure) p)
.collect(Collectors.toList());
this.assignmentManager.setupRIT(ritList);
// Start RegionServerTracker with listing of servers found with exiting SCPs -- these should
// be registered in the deadServers set -- and with the list of servernames out on the
// filesystem that COULD BE 'alive' (we'll schedule SCPs for each and let SCP figure it out).
// We also pass dirs that are already 'splitting'... so we can do some checks down in tracker.
// TODO: Generate the splitting and live Set in one pass instead of two as we currently do.
this.regionServerTracker = new RegionServerTracker(zooKeeper, this, this.serverManager);
this.regionServerTracker.start(
procsByType.getOrDefault(ServerCrashProcedure.class, Collections.emptyList()).stream()
.map(p -> (ServerCrashProcedure) p).map(p -> p.getServerName()).collect(Collectors.toSet()),
walManager.getLiveServersFromWALDir(), walManager.getSplittingServersFromWALDir());
// This manager will be started AFTER hbase:meta is confirmed on line.
// hbase.mirror.table.state.to.zookeeper is so hbase1 clients can connect. They read table
// state from zookeeper while hbase2 reads it from hbase:meta. Disable if no hbase1 clients.
this.tableStateManager =
this.conf.getBoolean(MirroringTableStateManager.MIRROR_TABLE_STATE_TO_ZK_KEY, true)
?
new MirroringTableStateManager(this):
new TableStateManager(this);
status.setStatus("Initializing ZK system trackers");
initializeZKBasedSystemTrackers();
status.setStatus("Loading last flushed sequence id of regions");
try {
this.serverManager.loadLastFlushedSequenceIds();
} catch (IOException e) {
LOG.info("Failed to load last flushed sequence id of regions"
+ " from file system", e);
}
// Set ourselves as active Master now our claim has succeeded up in zk.
this.activeMaster = true;
// Start the Zombie master detector after setting master as active, see HBASE-21535
Thread zombieDetector = new Thread(new InitializationMonitor(this),