12:43:39,599 AM [testsystem-akka.actor.default-dispatcher-6] [INFO] Slf4jLogger - Slf4jLogger started
12:43:39,889 AM [testsystem-akka.actor.default-dispatcher-6] [INFO] RepointableActorRef -  akkaDeadLetter Message [java.lang.String] from Actor[akka://testsystem/system/testActor-1#-536580417] to Actor[akka://testsystem/user/pingpongactor#228244157] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[akka://testsystem/user/pingpongactor#228244157] 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'.