From aab9e0b16ecc8fa00228c00c7ab90e55195cf5f4 Mon Sep 17 00:00:00 2001
From: Ayush Saxena <ayushsaxena@apache.org>
Date: Sun, 10 May 2020 11:43:04 +0530
Subject: [PATCH] HDFS-15250. Setting `dfs.client.use.datanode.hostname` to
 true can crash the system because of unhandled UnresolvedAddressException.
 Contributed by Ctest.

---
 .../org/apache/hadoop/hdfs/client/impl/BlockReaderFactory.java | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderFactory.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderFactory.java
index 2109e6e1b7..a3b611c1ca 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderFactory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/BlockReaderFactory.java
@@ -27,6 +27,7 @@
 import java.io.IOException;
 import java.lang.reflect.Constructor;
 import java.net.InetSocketAddress;
+import java.nio.channels.UnresolvedAddressException;
 import java.util.List;
 
 import com.google.common.io.ByteArrayDataOutput;
@@ -823,7 +824,7 @@ private BlockReaderPeer nextTcpPeer() throws IOException {
           datanode);
       LOG.trace("nextTcpPeer: created newConnectedPeer {}", peer);
       return new BlockReaderPeer(peer, false);
-    } catch (IOException e) {
+    } catch (IOException | UnresolvedAddressException e) {
       LOG.trace("nextTcpPeer: failed to create newConnectedPeer connected to"
           + "{}", datanode);
       throw e;