diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockPoolManager.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockPoolManager.java
index 390577f8b5..95bc2d6c23 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockPoolManager.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/BlockPoolManager.java
@@ -158,7 +158,7 @@ void refreshNamenodes(Configuration conf)
       newLifelineAddressMap =
           DFSUtil.getNNLifelineRpcAddressesForCluster(conf);
     } catch (IOException ioe) {
-      LOG.warn("Unable to get NameNode addresses.");
+      LOG.warn("Unable to get NameNode addresses.", ioe);
     }
 
     if (newAddressMap == null || newAddressMap.isEmpty()) {