ZOOKEEPER-608. Receipt of ACK from observer should not be logged as ERROR (henry via mahadev)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/zookeeper/trunk@901496 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -199,6 +199,9 @@ BUGFIXES:
   ZOOKEEPER-651: Log exception trace in QuorumCnxManager.SendWorker 
   (flavio via henry)
 
+  ZOOKEEPER-608. Receipt of ACK from observer should not be logged as ERROR
+  (henry via mahadev)
+
 IMPROVEMENTS:
   ZOOKEEPER-473. cleanup junit tests to eliminate false positives due to
   "socket reuse" and failure to close client (phunt via mahadev)

src/java/main/org/apache/zookeeper/server/quorum/LearnerHandler.java

@@ -367,7 +367,9 @@ public class LearnerHandler extends Thread {
                 switch (qp.getType()) {
                 case Leader.ACK:
                     if (this.learnerType == LearnerType.OBSERVER) {
-                        LOG.error("Received ACK from Observer  " + this.sid);
+                        if (LOG.isDebugEnabled()) {
+                            LOG.debug("Received ACK from Observer  " + this.sid);
+                        }
                     }
                     leader.processAck(this.sid, qp.getZxid(), sock.getLocalSocketAddress());
                     break;