HDFS-3008. svn merge -c 1293419 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1293421 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -65,6 +65,8 @@ Release 0.23.2 - UNRELEASED
     dfs.client.block.write.replace-datanode-on-failure.enable should be true.
     (szetszwo)
 
+    HDFS-3008. Negative caching of local addrs doesn't work. (eli)
+
 Release 0.23.1 - 2012-02-17 
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -524,11 +524,12 @@ public class DFSClient implements java.io.Closeable {
   private static boolean isLocalAddress(InetSocketAddress targetAddr) {
     InetAddress addr = targetAddr.getAddress();
     Boolean cached = localAddrMap.get(addr.getHostAddress());
-    if (cached != null && cached) {
+    if (cached != null) {
       if (LOG.isTraceEnabled()) {
-        LOG.trace("Address " + targetAddr + " is local");
+        LOG.trace("Address " + targetAddr +
+                  (cached ? " is local" : " is not local"));
       }
-      return true;
+      return cached;
     }
 
     // Check if the address is any local or loop back
@@ -543,7 +544,8 @@ public class DFSClient implements java.io.Closeable {
       }
     }
     if (LOG.isTraceEnabled()) {
-      LOG.trace("Address " + targetAddr + " is local");
+      LOG.trace("Address " + targetAddr +
+                (local ? " is local" : " is not local"));
     }
     localAddrMap.put(addr.getHostAddress(), local);
     return local;