HADOOP-506. Ignore heartbeats from stale tasktrackers. Contributed by Sanjay.

git-svn-id: https://svn.apache.org/repos/asf/lucene/hadoop/trunk@453392 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -139,6 +139,9 @@ Trunk (unreleased changes)
     job statistics are not lost after 24 hours and/or when the
     jobtracker is restarted.  (Sanjay Dahiya via cutting)
 
+34. HADOOP-506.  Ignore heartbeats from stale task trackers.
+   (Sanjay Dahiya via cutting)
+
 
 Release 0.6.2 - 2006-09-18
 

src/java/org/apache/hadoop/mapred/JobTracker.java

@@ -751,6 +751,8 @@ public class JobTracker implements MRConstants, InterTrackerProtocol, JobSubmiss
                 } else {
                     // If not first contact, there should be some record of the tracker
                     if (!seenBefore) {
+                        LOG.warn("Status from unknown Tracker : " + trackerName);
+                        taskTrackers.remove(trackerName); 
                         return InterTrackerProtocol.UNKNOWN_TASKTRACKER;
                     }
                 }