From 3ab2e79ad7786623798c5c8816fcdb4173b09da1 Mon Sep 17 00:00:00 2001
From: Steve Loughran <stevel@apache.org>
Date: Sat, 8 Oct 2011 10:41:56 +0000
Subject: [PATCH] HDFS-2209 datanode connection failure logging

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1180353 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt        |  3 +++
 .../org/apache/hadoop/hdfs/DFSInputStream.java     | 14 +++++++++-----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 1d63cab059..3aa6b1daa3 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -798,6 +798,9 @@ Release 0.23.0 - Unreleased
 
     HDFS-2209. Make MiniDFS easier to embed in other apps. (stevel)
 
+    HDFS-2205. Log message for failed connection to datanode is not
+    followed by a success message. (Ravi Prakash via stevel)
+
   OPTIMIZATIONS
 
     HDFS-1458. Improve checkpoint performance by avoiding unnecessary image
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
index e446122efb..2964ccb5a7 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
@@ -388,6 +388,8 @@ private synchronized DatanodeInfo blockSeekTo(long target) throws IOException {
     DatanodeInfo chosenNode = null;
     int refetchToken = 1; // only need to get a new access token once
     
+    boolean connectFailedOnce = false;
+
     while (true) {
       //
       // Compute desired block
@@ -409,6 +411,10 @@ private synchronized DatanodeInfo blockSeekTo(long target) throws IOException {
             accessToken,
             offsetIntoBlock, blk.getNumBytes() - offsetIntoBlock,
             buffersize, verifyChecksum, dfsClient.clientName);
+        if(connectFailedOnce) {
+          DFSClient.LOG.info("Successfully connected to " + targetAddr +
+                             " for block " + blk.getBlockId());
+        }
         return chosenNode;
       } catch (IOException ex) {
         if (ex instanceof InvalidBlockTokenException && refetchToken > 0) {
@@ -428,11 +434,9 @@ private synchronized DatanodeInfo blockSeekTo(long target) throws IOException {
           refetchToken--;
           fetchBlockAt(target);
         } else {
-          DFSClient.LOG.warn("Failed to connect to " + targetAddr
-              + ", add to deadNodes and continue " + ex);
-          if (DFSClient.LOG.isDebugEnabled()) {
-            DFSClient.LOG.debug("Connection failure ", ex);
-          }
+          connectFailedOnce = true;
+          DFSClient.LOG.warn("Failed to connect to " + targetAddr + " for block"
+            + ", add to deadNodes and continue. " + ex, ex);
           // Put chosen node into dead list, continue
           addToDeadNodes(chosenNode);
         }