HDFS-7961. Trigger full block report after hot swapping disk. Contributed by Eddy Xu.

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

@@ -1251,6 +1251,8 @@ Release 2.7.0 - UNRELEASED
     HDFS-7960. The full block report should prune zombie storages even if
     they're not empty. (cmccabe and Eddy Xu via wang)
 
+    HDFS-7961. Trigger full block report after hot swapping disk. (Eddy Xu via wang)
+
     BREAKDOWN OF HDFS-7584 SUBTASKS AND RELATED JIRAS
 
       HDFS-7720. Quota by Storage Type API, tools and ClientNameNode

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java

@@ -634,6 +634,10 @@ public class DataNode extends ReconfigurableBase
       conf.set(DFS_DATANODE_DATA_DIR_KEY,
           Joiner.on(",").join(effectiveVolumes));
       dataDirs = getStorageLocations(conf);
+
+      // Send a full block report to let NN acknowledge the volume changes.
+      triggerBlockReport(new BlockReportOptions.Factory()
+          .setIncremental(false).build());
     }
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeHotSwapVolumes.java

@@ -34,12 +34,16 @@ import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.MiniDFSNNTopology;
 import org.apache.hadoop.hdfs.protocol.BlockListAsLongs;
+import org.apache.hadoop.hdfs.protocolPB.DatanodeProtocolClientSideTranslatorPB;
 import org.apache.hadoop.hdfs.server.common.Storage;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeSpi;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetTestUtil;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsVolumeImpl;
+import org.apache.hadoop.hdfs.server.protocol.BlockReportContext;
+import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
 import org.apache.hadoop.hdfs.server.protocol.DatanodeStorage;
+import org.apache.hadoop.hdfs.server.protocol.StorageBlockReport;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.junit.After;
 import org.junit.Test;
@@ -59,6 +63,7 @@ import java.util.concurrent.TimeoutException;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.mockito.Mockito;
 
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_DATA_DIR_KEY;
 import static org.hamcrest.CoreMatchers.anyOf;
@@ -70,6 +75,9 @@ import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
+import static org.mockito.Matchers.any;
+import static org.mockito.Matchers.anyString;
+import static org.mockito.Mockito.timeout;
 
 public class TestDataNodeHotSwapVolumes {
   private static final Log LOG = LogFactory.getLog(
@@ -702,4 +710,38 @@ public class TestDataNodeHotSwapVolumes {
     // More data has been written to this volume.
     assertTrue(restoredVolume.getDfsUsed() > used);
   }
+
+  /** Test that a full block report is sent after hot swapping volumes */
+  @Test(timeout=100000)
+  public void testFullBlockReportAfterRemovingVolumes()
+      throws IOException, ReconfigurationException {
+
+    Configuration conf = new Configuration();
+    conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, BLOCK_SIZE);
+
+    // Similar to TestTriggerBlockReport, set a really long value for
+    // dfs.heartbeat.interval, so that incremental block reports and heartbeats
+    // won't be sent during this test unless they're triggered
+    // manually.
+    conf.setLong(DFSConfigKeys.DFS_BLOCKREPORT_INTERVAL_MSEC_KEY, 10800000L);
+    conf.setLong(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1080L);
+
+    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(2).build();
+    cluster.waitActive();
+
+    final DataNode dn = cluster.getDataNodes().get(0);
+    DatanodeProtocolClientSideTranslatorPB spy =
+        DataNodeTestUtils.spyOnBposToNN(dn, cluster.getNameNode());
+
+    // Remove a data dir from datanode
+    File dataDirToKeep = new File(cluster.getDataDirectory(), "data1");
+    dn.reconfigurePropertyImpl(DFS_DATANODE_DATA_DIR_KEY, dataDirToKeep.toString());
+
+    // We should get 1 full report
+    Mockito.verify(spy, timeout(60000).times(1)).blockReport(
+        any(DatanodeRegistration.class),
+        anyString(),
+        any(StorageBlockReport[].class),
+        any(BlockReportContext.class));
+  }
 }