05:12:50,597 PM [testsystem-akka.actor.default-dispatcher-5] [INFO] Slf4jLogger - Slf4jLogger started 05:12:50,915 PM [testsystem-akka.actor.default-dispatcher-5] [INFO] RepointableActorRef - akkaDeadLetter Message [java.lang.String] from Actor[akka://testsystem/system/testActor-30#494409554] to Actor[akka://testsystem/user/pingpongactor#1868872579] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[akka://testsystem/user/pingpongactor#1868872579] 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'. 05:12:50,920 PM [testsystem-akka.actor.default-dispatcher-8] [INFO] CoordinatedShutdown - Running CoordinatedShutdown with reason [ActorSystemTerminateReason]