12:39:44,659 AM [testsystem-akka.actor.default-dispatcher-6] [INFO] Slf4jLogger - Slf4jLogger started
12:39:44,937 AM [testsystem-akka.actor.default-dispatcher-7] [INFO] RepointableActorRef -  akkaDeadLetter Message [java.lang.String] from Actor[akka://testsystem/system/testActor-51#907329237] to Actor[akka://testsystem/user/pingpongactor#-1400701139] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[akka://testsystem/user/pingpongactor#-1400701139] may have terminated unexpectedly. This logging can be turned off or adjusted with configuration settings 'akka.log-dead-letters' and 'akka.log-dead-letters-during-shutdown'.
12:39:44,941 AM [testsystem-akka.actor.default-dispatcher-8] [INFO] CoordinatedShutdown - Running CoordinatedShutdown with reason [ActorSystemTerminateReason]