TEZ-3978. DAGClientServer Socket exception when localhost name lookup failures (Jonathan Eagles via jlowe)

Signed-off-by: Jason Lowe <jlowe@apache.org>
diff --git a/tez-dag/src/main/java/org/apache/tez/dag/api/client/DAGClientServer.java b/tez-dag/src/main/java/org/apache/tez/dag/api/client/DAGClientServer.java
index 14de870..2040244 100644
--- a/tez-dag/src/main/java/org/apache/tez/dag/api/client/DAGClientServer.java
+++ b/tez-dag/src/main/java/org/apache/tez/dag/api/client/DAGClientServer.java
@@ -128,7 +128,7 @@
       BlockingService blockingService, String portRangeConfig) throws IOException {
     RPC.setProtocolEngine(conf, pbProtocol, ProtobufRpcEngine.class);
     RPC.Server server = new RPC.Builder(conf).setProtocol(pbProtocol)
-        .setInstance(blockingService).setBindAddress(addr.getHostName())
+        .setInstance(blockingService).setBindAddress(addr.getHostString())
         .setPort(addr.getPort()).setNumHandlers(numHandlers).setVerbose(false)
         .setPortRangeConfig(portRangeConfig).setSecretManager(secretManager)
         .build();