HDFS-15170. EC: Block gets marked as CORRUPT in case of failover and pipeline recovery. Contributed by Ayush Saxena.

Signed-off-by: Wei-Chiu Chuang <weichiu@apache.org>
(cherry picked from commit 5e5c53070f1946b86e49c039e1f5ae42e5d022cb)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/BlockManager.java

@@ -1856,6 +1856,16 @@ public class BlockManager implements BlockStatsMXBean {
     // In case of 3, rbw block will be deleted and valid block can be replicated
     if (hasEnoughLiveReplicas || hasMoreCorruptReplicas
         || corruptedDuringWrite) {
+      if (b.getStored().isStriped()) {
+        // If the block is an EC block, the whole block group is marked
+        // corrupted, so if this block is getting deleted, remove the block
+        // from corrupt replica map explicitly, since removal of the
+        // block from corrupt replicas may be delayed if the blocks are on
+        // stale storage due to failover or any other reason.
+        corruptReplicas.removeFromCorruptReplicasMap(b.getStored(), node);
+        BlockInfoStriped blk = (BlockInfoStriped) getStoredBlock(b.getStored());
+        blk.removeStorage(storageInfo);
+      }
       // the block is over-replicated so invalidate the replicas immediately
       invalidateBlock(b, node, numberOfReplicas);
     } else if (isPopulatingReplQueues()) {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestErasureCodingCorruption.java

@@ -0,0 +1,91 @@
+/**
+ * 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.hdfs.server.blockmanagement;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FSDataOutputStream;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.hdfs.MiniDFSNNTopology;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.Test;
+
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_CORRUPT_BLOCK_DELETE_IMMEDIATELY_ENABLED;
+
+/**
+ * In case of Erasure Coding the entire block group is marked corrupted, in
+ * case there is a failure during write, the replica when reported to
+ * Namenode marks the block group as corrupt, but since the file is complete
+ * and the replica has a lower gen stamp, the replica is marked to be
+ * deleted, but in case the replica is on stale storage(Namenode marks
+ * datanodes as stale in case of failover, etc), then the deletion of block
+ * is postponed and hence the block group isn't removed from the corrupt
+ * replica map. So, in case of striped blocks, if the replica is suppose to
+ * get deleted, explicitly remove the block group from corrupt-replica map.
+ */
+public class TestErasureCodingCorruption {
+
+  @Test
+  public void testCorruptionDuringFailover() throws Exception {
+    Configuration conf = new Configuration();
+    // Set removal of corrupt replicas immediately as false, to trigger this
+    // case.
+    conf.setBoolean(DFS_NAMENODE_CORRUPT_BLOCK_DELETE_IMMEDIATELY_ENABLED,
+        false);
+    try (MiniDFSCluster cluster = new MiniDFSCluster
+        .Builder(conf)
+        .nnTopology(MiniDFSNNTopology.simpleHATopology())
+        .numDataNodes(8)
+        .build()) {
+      cluster.transitionToActive(0);
+      cluster.waitActive();
+
+      DistributedFileSystem dfs = cluster.getFileSystem(0);
+      dfs.mkdirs(new Path("/dir"));
+      dfs.setErasureCodingPolicy(new Path("/dir"), "RS-6-3-1024k");
+
+      FSDataOutputStream out = dfs.create(new Path("/dir/file"));
+      // Write more than one stripe, so that data can get flushed to all
+      // datanodes.
+      for (int i = 0; i < 15 * 1024 * 1024; i++) {
+        out.write(i);
+      }
+
+      // Stop one datanode, so as to trigger update pipeline.
+      MiniDFSCluster.DataNodeProperties dn = cluster.stopDataNode(0);
+      // Write some more data and close the file.
+      for (int i = 0; i < 7 * 1024 * 1024; i++) {
+        out.write(i);
+      }
+      out.close();
+
+      BlockManager bm = cluster.getNamesystem(0).getBlockManager();
+
+      // Transition to standby and then to active.
+      cluster.transitionToStandby(0);
+      cluster.transitionToActive(0);
+
+      // Restart the stopped Datanode, this datanode would report a replica
+      // that failed during write.
+      cluster.restartDataNode(dn);
+      GenericTestUtils
+          .waitFor(() -> bm.getCorruptECBlockGroups() == 0, 100, 10000);
+    }
+  }
+}