2019-01-18 10:21:29.679 [  78]     GENERAL INFO    Test connecting to Amazon Aurora (MySQL compatible) database started...
2019-01-18 10:21:29.683 [  78]      LOADER INFO    Max JDBC Connections changed to 20
2019-01-18 10:21:29.684 [  78]      LOADER INFO    Max Connection Threads changed to 20
2019-01-18 10:21:29.685 [  78]      LOADER INFO    minEvictableTimeMillis changed to 30000
2019-01-18 10:21:33.512 [  78]      LOADER ERROR   Connection to 'jdbc:mysql://xyz.ccn3axbfnoy3.us-east-1.rds.amazonaws.com:3306' wasn't established. ERROR: code: 0; message: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
2019-01-18 10:21:33.512 [  78]     GENERAL INFO    Test connecting to Amazon Aurora (MySQL compatible) database finished in 0:00:03.833 sec with memory consumption of 667.61 MB (661.54 MB .. 667.61 MB).
2019-01-18 10:21:33.513 [  78]     GENERAL INFO    Test connecting to Amazon Aurora (MySQL compatible) database statistics:
    GENERAL: 0:00:03.834 sec
2019-01-18 10:21:33.513 [  17]     GENERAL ERROR   com.amazon.sct.dbloader.DbLoaderHandledException: Connection wasn't established. Check connection properties.
java.util.concurrent.ExecutionException: com.amazon.sct.dbloader.DbLoaderHandledException: Connection wasn't established. Check connection properties.
    at java.util.concurrent.FutureTask.report(FutureTask.java:122)
    at java.util.concurrent.FutureTask.get(FutureTask.java:192)
    at com.amazon.sct.task.launcher.CommonTaskLauncher.lambda$run$0(CommonTaskLauncher.java:30)
    at com.sun.javafx.binding.ExpressionHelper$Generic.fireValueChangedEvent(ExpressionHelper.java:361)
    at com.sun.javafx.binding.ExpressionHelper.fireValueChangedEvent(ExpressionHelper.java:81)
    at javafx.beans.property.ObjectPropertyBase.fireValueChangedEvent(ObjectPropertyBase.java:105)
    at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:112)
    at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:146)
    at javafx.concurrent.Task.setState(Task.java:696)
    at javafx.concurrent.Task$TaskCallable.lambda$call$502(Task.java:1453)
    at com.sun.javafx.application.PlatformImpl.lambda$null$172(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$173(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._enterNestedEventLoopImpl(Native Method)
    at com.sun.glass.ui.win.WinApplication._enterNestedEventLoop(WinApplication.java:204)
    at com.sun.glass.ui.Application.enterNestedEventLoop(Application.java:511)
    at com.sun.glass.ui.EventLoop.enter(EventLoop.java:107)
    at com.sun.javafx.tk.quantum.QuantumToolkit.enterNestedEventLoop(QuantumToolkit.java:590)
    at javafx.stage.Stage.showAndWait(Stage.java:474)
    at javafx.scene.control.HeavyweightDialog.showAndWait(HeavyweightDialog.java:162)
    at javafx.scene.control.Dialog.showAndWait(Dialog.java:341)
    at com.amazon.sct.handler.CreateConnectionHandler.createConnection(CreateConnectionHandler.java:37)
    at com.amazon.sct.viewmodel.AppViewModel.createConnection(AppViewModel.java:1294)
    at com.amazon.sct.viewmodel.AppViewModel.createTargetConnection(AppViewModel.java:656)
    at com.amazon.sct.view.AppView.loadTarget(AppView.java:291)
    at com.amazon.sct.view.AppView.lambda$initConnectionMenusBindings$22(AppView.java:918)
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
    at javafx.event.Event.fireEvent(Event.java:198)
    at javafx.scene.Scene$MouseHandler.process(Scene.java:3757)
    at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485)
    at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
    at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494)
    at

C:Usersabc>nslookup xyz-cluster.cluster-ccn3axbfnoy3.us-east-1.rds.amazonaws.com
Non-authoritative answer:
Name:    xyz.ccn3axbfnoy3.us-east-1.rds.amazonaws.com
Address:  10.AA.Y.XXX
Aliases:  xyz-cluster.cluster-ccn3axbfnoy3.us-east-1.rds.amazonaws.com