diff --git a/server/src/com/cloud/network/lb/LoadBalancingRulesManagerImpl.java b/server/src/com/cloud/network/lb/LoadBalancingRulesManagerImpl.java
index 3f7b70ffffc..afbcfa0831b 100755
--- a/server/src/com/cloud/network/lb/LoadBalancingRulesManagerImpl.java
+++ b/server/src/com/cloud/network/lb/LoadBalancingRulesManagerImpl.java
@@ -967,6 +967,11 @@ public class LoadBalancingRulesManagerImpl<Type> extends ManagerBase implements
         }
 
         List<UserVm> vmsToAdd = new ArrayList<UserVm>();
+        
+        if (instanceIds == null || instanceIds.isEmpty()) {
+            s_logger.warn("List of vms to assign to the lb, is empty");
+            return false;
+        }
 
         for (Long instanceId : instanceIds) {
             if (mappedInstanceIds.contains(instanceId)) {