Nie udało się wysłać wiadomość zdalnego uczestnika akka

Jestem nowy w zdalnym zarządzaniu akka i staram się po prostu wysłać wiadomość do zdalnego wykonawcy i uzyskać odpowiedź w odpowiedzi. Mam 2 systemy podmiotów na lokalnym hoście - różne porty: мастерсистема i system pracy. Stworzył aktora w systemie produkcyjnym i próbował wyślij wiadomość na adres zdalny. Ale wciąż otrzymuję komunikat "znaleziono martwe litery"! Będę wdzięczny za każdą pomoc. Dziękuję!

MainMaster.java

package pi_swarm_approx;

import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.ActorSystem;
import akka.actor.UntypedActor;
import com.typesafe.config.ConfigFactory;

public class MainMaster extends UntypedActor{
    ActorSystem system;
    ActorRef actor;
    ActorSelection remoteActor;
    
    public MainMaster() {
        system = ActorSystem.create("MasterSystem", ConfigFactory.load("master"));
        System.out.println("MasterSystem created");
        MainWorker mw = new MainWorker();
        System.out.println("MainWorker obj created");
        remoteActor = mw.system.actorSelection("akka://WorkerSystem@localhost:2552/user/workerActor");
        
        System.out.println("Remote actor created");    
        remoteActor.tell("hello", getSelf());
        System.out.println("Message sent to remote actor");
    }
    
    public void onReceive(Object msg) {
        if (msg != null) {
            System.out.println("Got it back");
        }
         else {
            unhandled(msg);
            getContext().stop(getSelf());
         }
    }
}

MainWorker.java

package pi_swarm_approx;

import akka.actor.ActorSystem;
import akka.actor.ActorRef;
import com.typesafe.config.ConfigFactory;
import akka.actor.Props;

public class MainWorker {
    ActorSystem system;
    ActorRef actor;
    public MainWorker() {
        this.system = ActorSystem.create("WorkerSystem", ConfigFactory.load("worker"));
        actor = system.actorOf(Props.create(Worker.class), "workerActor");
    }
}

Worker.java

package pi_swarm_approx;

import akka.actor.UntypedActor;

public class Worker extends UntypedActor {  
    public void onReceive(Object msg) {
        System.out.println("Worker actor got message");
        if (msg != null) {
            getSender().tell("Request processed", getSelf());
        }
         else {
            unhandled(msg);
         }
        getContext().stop(getSelf());
    }
}

mistrz.konf

akka {
  actor {
    provider = "cluster"
  }
  remote {
  transport = ["akka.remote.netty.tcp"]
    netty.tcp {
      hostname = "localhost"
      port = 2551
    }
  }
  
  clustering {
    cluster.name = "MasterSystem"
    role = "master"
  }
 }

roboczy.konf

akka {
  actor {
    provider = "cluster"
    deployment {
        /workerActor {
          remote = "akka.tcp://WorkerSystem@localhost:2552"
        }
  }
}

Wyjście

In main
MasterSystem created
MainWorker obj created
Remote actor created
Message sent to remote actor
[INFO] [11/22/2021 16:01:34.531] [WorkerSystem-akka.actor.default-dispatcher-5] [akka://WorkerSystem/deadLetters] Message [java.lang.String] from Actor[akka://Main/user/app#402333018] to Actor[akka://WorkerSystem/deadLetters] was not delivered. [1] dead letters encountered. If this is not an expected behavior, then [Actor[akka://WorkerSystem/deadLetters]] 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'.
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