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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.master;
20  
21  import java.io.File;
22  import java.io.IOException;
23  import java.util.List;
24  
25  import org.apache.commons.cli.CommandLine;
26  import org.apache.commons.cli.GnuParser;
27  import org.apache.commons.cli.Options;
28  import org.apache.commons.cli.ParseException;
29  import org.apache.commons.logging.Log;
30  import org.apache.commons.logging.LogFactory;
31  import org.apache.hadoop.classification.InterfaceAudience;
32  import org.apache.hadoop.conf.Configuration;
33  import org.apache.hadoop.fs.FileSystem;
34  import org.apache.hadoop.hbase.MasterNotRunningException;
35  import org.apache.hadoop.hbase.ZNodeClearer;
36  import org.apache.hadoop.hbase.HConstants;
37  import org.apache.hadoop.hbase.LocalHBaseCluster;
38  import org.apache.hadoop.hbase.ZooKeeperConnectionException;
39  import org.apache.hadoop.hbase.client.HBaseAdmin;
40  import org.apache.hadoop.hbase.regionserver.HRegionServer;
41  import org.apache.hadoop.hbase.util.JVMClusterUtil;
42  import org.apache.hadoop.hbase.util.ServerCommandLine;
43  import org.apache.hadoop.hbase.zookeeper.MiniZooKeeperCluster;
44  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
45  import org.apache.zookeeper.KeeperException;
46  
47  @InterfaceAudience.Private
48  public class HMasterCommandLine extends ServerCommandLine {
49    private static final Log LOG = LogFactory.getLog(HMasterCommandLine.class);
50  
51    private static final String USAGE =
52      "Usage: Master [opts] start|stop|clear\n" +
53      " start  Start Master. If local mode, start Master and RegionServer in same JVM\n" +
54      " stop   Start cluster shutdown; Master signals RegionServer shutdown\n" +
55      " clear  Delete the master znode in ZooKeeper after a master crashes\n "+
56      " where [opts] are:\n" +
57      "   --minRegionServers=<servers>   Minimum RegionServers needed to host user tables.\n" +
58      "   --localRegionServers=<servers> " +
59        "RegionServers to start in master process when in standalone mode.\n" +
60      "   --masters=<servers>            Masters to start in this process.\n" +
61      "   --backup                       Master should start in backup mode";
62  
63    private final Class<? extends HMaster> masterClass;
64  
65    public HMasterCommandLine(Class<? extends HMaster> masterClass) {
66      this.masterClass = masterClass;
67    }
68  
69    protected String getUsage() {
70      return USAGE;
71    }
72  
73  
74    public int run(String args[]) throws Exception {
75      Options opt = new Options();
76      opt.addOption("localRegionServers", true,
77        "RegionServers to start in master process when running standalone");
78      opt.addOption("masters", true, "Masters to start in this process");
79      opt.addOption("minRegionServers", true, "Minimum RegionServers needed to host user tables");
80      opt.addOption("backup", false, "Do not try to become HMaster until the primary fails");
81  
82      CommandLine cmd;
83      try {
84        cmd = new GnuParser().parse(opt, args);
85      } catch (ParseException e) {
86        LOG.error("Could not parse: ", e);
87        usage(null);
88        return 1;
89      }
90  
91  
92      if (cmd.hasOption("minRegionServers")) {
93        String val = cmd.getOptionValue("minRegionServers");
94        getConf().setInt("hbase.regions.server.count.min",
95                    Integer.valueOf(val));
96        LOG.debug("minRegionServers set to " + val);
97      }
98  
99      // minRegionServers used to be minServers.  Support it too.
100     if (cmd.hasOption("minServers")) {
101       String val = cmd.getOptionValue("minServers");
102       getConf().setInt("hbase.regions.server.count.min",
103                   Integer.valueOf(val));
104       LOG.debug("minServers set to " + val);
105     }
106 
107     // check if we are the backup master - override the conf if so
108     if (cmd.hasOption("backup")) {
109       getConf().setBoolean(HConstants.MASTER_TYPE_BACKUP, true);
110     }
111 
112     // How many regionservers to startup in this process (we run regionservers in same process as
113     // master when we are in local/standalone mode. Useful testing)
114     if (cmd.hasOption("localRegionServers")) {
115       String val = cmd.getOptionValue("localRegionServers");
116       getConf().setInt("hbase.regionservers", Integer.valueOf(val));
117       LOG.debug("localRegionServers set to " + val);
118     }
119     // How many masters to startup inside this process; useful testing
120     if (cmd.hasOption("masters")) {
121       String val = cmd.getOptionValue("masters");
122       getConf().setInt("hbase.masters", Integer.valueOf(val));
123       LOG.debug("masters set to " + val);
124     }
125 
126     List<String> remainingArgs = cmd.getArgList();
127     if (remainingArgs.size() != 1) {
128       usage(null);
129       return 1;
130     }
131 
132     String command = remainingArgs.get(0);
133 
134     if ("start".equals(command)) {
135       return startMaster();
136     } else if ("stop".equals(command)) {
137       return stopMaster();
138     } else if ("clear".equals(command)) {
139       return (ZNodeClearer.clear(getConf()) ? 0 : 1);
140     } else {
141       usage("Invalid command: " + command);
142       return 1;
143     }
144   }
145 
146   private int startMaster() {
147     Configuration conf = getConf();
148     try {
149       // If 'local', defer to LocalHBaseCluster instance.  Starts master
150       // and regionserver both in the one JVM.
151       if (LocalHBaseCluster.isLocal(conf)) {
152         final MiniZooKeeperCluster zooKeeperCluster = new MiniZooKeeperCluster(conf);
153         File zkDataPath = new File(conf.get(HConstants.ZOOKEEPER_DATA_DIR));
154         int zkClientPort = conf.getInt(HConstants.ZOOKEEPER_CLIENT_PORT, 0);
155         if (zkClientPort == 0) {
156           throw new IOException("No config value for "
157               + HConstants.ZOOKEEPER_CLIENT_PORT);
158         }
159         zooKeeperCluster.setDefaultClientPort(zkClientPort);
160 
161         // login the zookeeper server principal (if using security)
162         ZKUtil.loginServer(conf, "hbase.zookeeper.server.keytab.file",
163           "hbase.zookeeper.server.kerberos.principal", null);
164 
165         int clientPort = zooKeeperCluster.startup(zkDataPath);
166         if (clientPort != zkClientPort) {
167           String errorMsg = "Could not start ZK at requested port of " +
168             zkClientPort + ".  ZK was started at port: " + clientPort +
169             ".  Aborting as clients (e.g. shell) will not be able to find " +
170             "this ZK quorum.";
171           System.err.println(errorMsg);
172           throw new IOException(errorMsg);
173         }
174         conf.set(HConstants.ZOOKEEPER_CLIENT_PORT,
175                  Integer.toString(clientPort));
176         conf.setInt(HConstants.ZK_SESSION_TIMEOUT, 10 *1000);
177         // Need to have the zk cluster shutdown when master is shutdown.
178         // Run a subclass that does the zk cluster shutdown on its way out.
179         LocalHBaseCluster cluster = new LocalHBaseCluster(conf, conf.getInt("hbase.masters", 1),
180           conf.getInt("hbase.regionservers", 1), LocalHMaster.class, HRegionServer.class);
181         ((LocalHMaster)cluster.getMaster(0)).setZKCluster(zooKeeperCluster);
182         cluster.startup();
183         waitOnMasterThreads(cluster);
184       } else {
185         logProcessInfo(getConf());
186         HMaster master = HMaster.constructMaster(masterClass, conf);
187         if (master.isStopped()) {
188           LOG.info("Won't bring the Master up as a shutdown is requested");
189           return 1;
190         }
191         master.start();
192         master.join();
193         if(master.isAborted())
194           throw new RuntimeException("HMaster Aborted");
195       }
196     } catch (Throwable t) {
197       LOG.error("Master exiting", t);
198       return 1;
199     }
200     return 0;
201   }
202 
203   private int stopMaster() {
204     HBaseAdmin adm = null;
205     try {
206       Configuration conf = getConf();
207       // Don't try more than once
208       conf.setInt(HConstants.HBASE_CLIENT_RETRIES_NUMBER, 1);
209       adm = new HBaseAdmin(getConf());
210     } catch (MasterNotRunningException e) {
211       LOG.error("Master not running");
212       return 1;
213     } catch (ZooKeeperConnectionException e) {
214       LOG.error("ZooKeeper not available");
215       return 1;
216     } catch (IOException e) {
217       LOG.error("Got IOException: " +e.getMessage(), e);
218       return 1;
219     }
220     try {
221       adm.shutdown();
222     } catch (Throwable t) {
223       LOG.error("Failed to stop master", t);
224       return 1;
225     }
226     return 0;
227   }
228 
229   private void waitOnMasterThreads(LocalHBaseCluster cluster) throws InterruptedException{
230     List<JVMClusterUtil.MasterThread> masters = cluster.getMasters();
231     List<JVMClusterUtil.RegionServerThread> regionservers = cluster.getRegionServers();
232 
233     if (masters != null) {
234       for (JVMClusterUtil.MasterThread t : masters) {
235         t.join();
236         if(t.getMaster().isAborted()) {
237           closeAllRegionServerThreads(regionservers);
238           throw new RuntimeException("HMaster Aborted");
239         }
240       }
241     }
242   }
243 
244   private static void closeAllRegionServerThreads(List<JVMClusterUtil.RegionServerThread> regionservers) {
245     for(JVMClusterUtil.RegionServerThread t : regionservers){
246       t.getRegionServer().stop("HMaster Aborted; Bringing down regions servers");
247     }
248   }
249 
250   /*
251    * Version of master that will shutdown the passed zk cluster on its way out.
252    */
253   public static class LocalHMaster extends HMaster {
254     private MiniZooKeeperCluster zkcluster = null;
255 
256     public LocalHMaster(Configuration conf)
257     throws IOException, KeeperException, InterruptedException {
258       super(conf);
259     }
260 
261     @Override
262     public void run() {
263       super.run();
264       if (this.zkcluster != null) {
265         try {
266           this.zkcluster.shutdown();
267         } catch (IOException e) {
268           e.printStackTrace();
269         }
270       }
271     }
272 
273     void setZKCluster(final MiniZooKeeperCluster zkcluster) {
274       this.zkcluster = zkcluster;
275     }
276   }
277 }