diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/ReplicaAccessorBuilder.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/ReplicaAccessorBuilder.java
index 2905df1245..14651f47f1 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/ReplicaAccessorBuilder.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/ReplicaAccessorBuilder.java
@@ -36,6 +36,9 @@ public abstract class ReplicaAccessorBuilder {
   public abstract ReplicaAccessorBuilder
       setBlock(long blockId, String blockPoolId);
 
+  /** Set the genstamp of the block which is being opened. */
+  public abstract ReplicaAccessorBuilder setGenerationStamp(long genstamp);
+
   /**
    * Set whether checksums must be verified.  Checksums should be skipped if
    * the user has disabled checksum verification in the configuration.  Users
diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index cb3b975db7..218f155e2b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -968,6 +968,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9112. Improve error message for Haadmin when multiple name service IDs
     are configured. (Anu Engineer via jing9)
 
+    HDFS-9132. Pass genstamp to ReplicaAccessorBuilder. (Colin Patrick McCabe via
+    Lei (Eddy) Xu)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
index b21261a01b..c9add534d8 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
@@ -383,6 +383,7 @@ private BlockReader tryToCreateExternalBlockReader() {
         ReplicaAccessor accessor = builder.
             setAllowShortCircuitReads(allowShortCircuitLocalReads).
             setBlock(block.getBlockId(), block.getBlockPoolId()).
+            setGenerationStamp(block.getGenerationStamp()).
             setBlockAccessToken(tokenBytes).
             setClientName(clientName).
             setConfiguration(configuration).
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestExternalBlockReader.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestExternalBlockReader.java
index 48d337b6f2..3a0e8e63ad 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestExternalBlockReader.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestExternalBlockReader.java
@@ -81,6 +81,7 @@ public static class SyntheticReplicaAccessorBuilder
     String fileName;
     long blockId;
     String blockPoolId;
+    long genstamp;
     boolean verifyChecksum;
     String clientName;
     boolean allowShortCircuit;
@@ -100,6 +101,12 @@ public ReplicaAccessorBuilder setBlock(long blockId, String blockPoolId) {
       return this;
     }
 
+    @Override
+    public ReplicaAccessorBuilder setGenerationStamp(long genstamp) {
+      this.genstamp = genstamp;
+      return this;
+    }
+
     @Override
     public ReplicaAccessorBuilder setVerifyChecksum(boolean verifyChecksum) {
       this.verifyChecksum = verifyChecksum;
@@ -154,12 +161,14 @@ public static class SyntheticReplicaAccessor extends ReplicaAccessor {
     int numCloses = 0;
     String error = "";
     String prefix = "";
+    final long genstamp;
 
     SyntheticReplicaAccessor(SyntheticReplicaAccessorBuilder builder) {
       this.length = builder.visibleLength;
       this.contents = DFSTestUtil.
           calculateFileContentsFromSeed(SEED, Ints.checkedCast(length));
       this.builder = builder;
+      this.genstamp = builder.genstamp;
       String uuid = this.builder.conf.
           get(SYNTHETIC_BLOCK_READER_TEST_UUID_KEY);
       LinkedList<SyntheticReplicaAccessor> accessorsList =
@@ -235,6 +244,10 @@ synchronized String getError() {
       return error;
     }
 
+    long getGenerationStamp() {
+      return genstamp;
+    }
+
     synchronized void addError(String text) {
       LOG.error("SyntheticReplicaAccessor error: " + text);
       error = error + prefix + text;
@@ -284,6 +297,8 @@ public void testExternalBlockReader() throws Exception {
       Assert.assertEquals(dfs.getClient().clientName,
           accessor.builder.clientName);
       Assert.assertEquals("/a", accessor.builder.fileName);
+      Assert.assertEquals(block.getGenerationStamp(),
+          accessor.getGenerationStamp());
       Assert.assertTrue(accessor.builder.verifyChecksum);
       Assert.assertEquals(1024L, accessor.builder.visibleLength);
       Assert.assertEquals(1024L, accessor.totalRead);