diff --git a/clean-cassandra.sh b/drop-keyspace.sh
similarity index 100%
rename from clean-cassandra.sh
rename to drop-keyspace.sh
diff --git a/src/main/java/net/floodlightcontroller/core/internal/Controller.java b/src/main/java/net/floodlightcontroller/core/internal/Controller.java
index 04e32e6..e5cb16f 100644
--- a/src/main/java/net/floodlightcontroller/core/internal/Controller.java
+++ b/src/main/java/net/floodlightcontroller/core/internal/Controller.java
@@ -560,7 +560,9 @@
                     removeSwitch(sw);
                 }
                 synchronized(roleChanger) {
-                	registryService.releaseControl(sw.getId());
+                	if (controlRequested) {
+                		registryService.releaseControl(sw.getId());
+                	}
                     connectedSwitches.remove(sw);
                 }
                 sw.setConnected(false);
@@ -795,8 +797,10 @@
                     dfuture);
 
         }
-        
+ 
+      	volatile Boolean controlRequested = Boolean.FALSE;
         protected void checkSwitchReady() {
+  
             if (state.hsState == HandshakeState.FEATURES_REPLY &&
                     state.hasDescription && state.hasGetConfigReply) {
                 
@@ -821,10 +825,12 @@
                     	
                     	//Request control of the switch from the global registry
                     	try {
+                    		controlRequested = Boolean.TRUE;
 							registryService.requestControl(sw.getId(), 
 									new RoleChangeCallback());
 						} catch (RegistryException e) {
 							log.debug("Registry error: {}", e.getMessage());
+							controlRequested = Boolean.FALSE;
 						}
                     	
                     	
@@ -858,6 +864,16 @@
                         state.firstRoleReplyReceived = true;
                     }
                 }
+                if (!controlRequested) {
+                	// yield to allow other thread(s) to release control
+                	try {
+						Thread.sleep(10);
+					} catch (InterruptedException e) {
+						// Ignore interruptions						
+					}
+                	// safer to bounce the switch to reconnect here than proceeding further
+                	sw.channel.close();
+                }
             }
         }
                 
diff --git a/src/main/java/net/floodlightcontroller/onoslistener/OnosPublisher.java b/src/main/java/net/floodlightcontroller/onoslistener/OnosPublisher.java
index c6fe108..9cb1c4f 100644
--- a/src/main/java/net/floodlightcontroller/onoslistener/OnosPublisher.java
+++ b/src/main/java/net/floodlightcontroller/onoslistener/OnosPublisher.java
@@ -48,7 +48,7 @@
 	protected static final String CleanupEnabled = "EnableCleanup";
 	protected IThreadPoolService threadPool;
 	
-	protected final int CLEANUP_TASK_INTERVAL = 999; // 999 ms
+	protected final int CLEANUP_TASK_INTERVAL = 10; // 10 sec
 	protected SingletonTask cleanupTask;
 	
 	/**
@@ -65,7 +65,7 @@
                 log.error("Error in cleanup thread", e);
             } finally {
                     cleanupTask.reschedule(CLEANUP_TASK_INTERVAL,
-                                              TimeUnit.MILLISECONDS);
+                                              TimeUnit.SECONDS);
             }
         }
 
@@ -74,7 +74,7 @@
 			// TODO Auto-generated method stub
 			
 			if (hasControl) {
-				log.debug("got control to set inactive sw {}", dpid);
+				log.debug("got control to set inactive sw {}", HexString.toHexString(dpid));
 				swStore.update(HexString.toHexString(dpid),SwitchState.INACTIVE, DM_OPERATION.UPDATE);
 			    registryService.releaseControl(dpid);	
 			}						
@@ -94,10 +94,10 @@
 				long dpid = HexString.toLong(sw.getDPID());
 				String controller = registryService.getControllerForSwitch(dpid);
 				if (controller == null) {
-					log.debug("request Control to set inactive sw {}", dpid);
+					log.debug("request Control to set inactive sw {}", HexString.toHexString(dpid));
 					registryService.requestControl(dpid, new SwitchCleanup());
 				} else {
-					log.debug("sw {} is controlled by controller: {}",dpid,controller);
+					log.debug("sw {} is controlled by controller: {}",HexString.toHexString(dpid),controller);
 				}
 			} catch (NumberFormatException e) {
 				// TODO Auto-generated catch block
@@ -223,10 +223,10 @@
 
 		deviceService.addListener(this);
 	       // Setup the Cleanup task. 
-		if (cleanupNeeded != null &&cleanupNeeded.equals("True")) {
+		if (cleanupNeeded == null || !cleanupNeeded.equals("False")) {
 				ScheduledExecutorService ses = threadPool.getScheduledExecutor();
 				cleanupTask = new SingletonTask(ses, new SwitchCleanup());
-				cleanupTask.reschedule(CLEANUP_TASK_INTERVAL, TimeUnit.MILLISECONDS);
+				cleanupTask.reschedule(CLEANUP_TASK_INTERVAL, TimeUnit.SECONDS);
 		}
 	}
 
diff --git a/src/main/java/net/onrc/onos/registry/controller/ZookeeperRegistry.java b/src/main/java/net/onrc/onos/registry/controller/ZookeeperRegistry.java
index f50bc82..b666db7 100644
--- a/src/main/java/net/onrc/onos/registry/controller/ZookeeperRegistry.java
+++ b/src/main/java/net/onrc/onos/registry/controller/ZookeeperRegistry.java
@@ -158,7 +158,7 @@
 		
 		if (switches.get(dpidStr) != null){
 			log.debug("Already contesting {}, returning", HexString.toHexString(dpid));
-			return;
+			throw new RegistryException("Already contesting control for " + dpidStr);
 		}
 		
 		LeaderLatch latch = new LeaderLatch(client, latchPath, controllerId);
diff --git a/src/main/resources/floodlightdefault.properties b/src/main/resources/floodlightdefault.properties
index 498fce5..5e1c13f 100644
--- a/src/main/resources/floodlightdefault.properties
+++ b/src/main/resources/floodlightdefault.properties
@@ -17,3 +17,4 @@
 net.floodlightcontroller.forwarding.Forwarding.idletimeout = 5
 net.floodlightcontroller.forwarding.Forwarding.hardtimeout = 0
 net.floodlightcontroller.onoslistener.OnosPublisher.dbconf = /tmp/cassandra.titan
+net.floodlightcontroller.onoslistener.OnosPublisher.EnableCleanup = True