View Javadoc

1   /**
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    * <p>
10   * http://www.apache.org/licenses/LICENSE-2.0
11   * <p>
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  
19  package org.apache.hadoop.hbase.chaos.actions;
20  
21  import org.apache.hadoop.hbase.ServerName;
22  import org.apache.hadoop.hbase.chaos.monkies.PolicyBasedChaosMonkey;
23  import org.apache.hadoop.hbase.util.FSUtils;
24  import org.apache.hadoop.hdfs.DFSClient;
25  import org.apache.hadoop.hdfs.DistributedFileSystem;
26  import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
27  import org.apache.hadoop.hdfs.protocol.HdfsConstants;
28  
29  import java.io.IOException;
30  import java.util.LinkedList;
31  import java.util.List;
32  
33  /**
34   * Action that restarts a random datanode.
35   */
36  public class RestartRandomDataNodeAction extends RestartActionBaseAction {
37    public RestartRandomDataNodeAction(long sleepTime) {
38      super(sleepTime);
39    }
40  
41    @Override
42    public void perform() throws Exception {
43      LOG.info("Performing action: Restart random data node");
44      ServerName server = PolicyBasedChaosMonkey.selectRandomItem(getDataNodes());
45      restartDataNode(server, sleepTime);
46    }
47  
48    public ServerName[] getDataNodes() throws IOException {
49      DistributedFileSystem fs = (DistributedFileSystem) FSUtils.getRootDir(getConf())
50          .getFileSystem(getConf());
51      DFSClient dfsClient = fs.getClient();
52      List<ServerName> hosts = new LinkedList<ServerName>();
53      for (DatanodeInfo dataNode: dfsClient.datanodeReport(HdfsConstants.DatanodeReportType.LIVE)) {
54        hosts.add(ServerName.valueOf(dataNode.getHostName(), -1, -1));
55      }
56      return hosts.toArray(new ServerName[hosts.size()]);
57    }
58  }