Akka UDP：127.0.0.1以外の宛先に送信するときに「無効な引数」

Question

akka.net.Udpを使用してUDPパケット（以下のコード）を送信します。私のローカルマシン（127.0.0.1）への送信はうまくいきますが、別のIPアドレスで同じコードを実行するとすぐに、akkaは「無効な引数」（下の出力）に苦情を返します。

何が問題になりますか？先として127.0.0.1と

[DEBUG] [06/20/2016 11:54:39.753] [main] [EventStream(akka://Main)] logger log1-Logging$DefaultLogger started 
[DEBUG] [06/20/2016 11:54:39.754] [main] [EventStream(akka://Main)] Default Loggers started 
[DEBUG] [06/20/2016 11:54:39.851] [Main-akka.actor.default-dispatcher-2] [akka://Main/system/IO-UDP-FF/selectors/$a/0] Successfully bound to [/127.0.0.1:2222] 
[INFO] [06/20/2016 11:54:40.783] [Main-akka.actor.default-dispatcher-5] [akka://Main/user/app/udp4] Send to /131.179.196.46:6363: ByteString(104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100) 
[DEBUG] [06/20/2016 11:54:40.789] [Main-akka.actor.default-dispatcher-5] [akka://Main/system/IO-UDP-FF/selectors/$a/0] Invalid argument 
[DEBUG] [06/20/2016 11:54:40.791] [Main-akka.actor.default-dispatcher-3] [akka://Main/system/IO-UDP-FF/selectors/$a/0] Closing DatagramChannel after being stopped 

出力：ローカル・マシン以外の宛先と

package debug 

import akka.actor.{Actor, ActorLogging, ActorRef, Props} 
import java.net.InetSocketAddress 
import akka.io.{IO, Udp} 
import akka.util.ByteString 


class SocketTest extends Actor with ActorLogging { 

    val dest = new InetSocketAddress("131.179.196.46", 6363)  // Invalid argument 
    // val dest = new InetSocketAddress("127.0.0.1", 6363)   // works fine 
    val udp = context.actorOf(Props(classOf[UDP4]), name="udp4") 

    // send 
    Thread.sleep(1000) 
    udp ! (dest, ByteString("hello world")) 

    Thread.sleep(99999) 
    def receive = {???} 

} 

class UDP4 extends Actor with ActorLogging { 

    val local = new InetSocketAddress("127.0.0.1", 2222) 

    import context.system 
    IO(Udp) ! Udp.Bind(self, local) 

    def receive: Receive = { 
    case Udp.Bound(local) => context.become(ready(sender)) 
    } 

    def ready(connection:ActorRef): Receive = { 
    case (remote:InetSocketAddress, data:ByteString) => { 
     log.info(s"Send to ${remote}: ${data}") 
     connection ! Udp.Send(data, remote) 
    } 
    case Udp.Received(data, remote) => log.info(s"Receive from ${remote}: ${data}") 
    case Udp.Unbind => connection ! Udp.Unbind 
    case Udp.Unbound => context.stop(self) 
    } 

} 

出力

[DEBUG] [06/20/2016 11:55:37.213] [main] [EventStream(akka://Main)] logger log1-Logging$DefaultLogger started 
[DEBUG] [06/20/2016 11:55:37.214] [main] [EventStream(akka://Main)] Default Loggers started 
[DEBUG] [06/20/2016 11:55:37.280] [Main-akka.actor.default-dispatcher-4] [akka://Main/system/IO-UDP-FF/selectors/$a/0] Successfully bound to [/127.0.0.1:2222] 
[INFO] [06/20/2016 11:55:38.234] [Main-akka.actor.default-dispatcher-2] [akka://Main/user/app/udp4] Send to /127.0.0.1:6363: ByteString(104, 101, 108, 108, 111, 32, 119, 111, 114, 108, 100) 

Answer 1

問題は、次の行である：

val local = new InetSocketAddress("127.0.0.1", 2222) 

req

val local = new InetSocketAddress("0.0.0.0", 2222) 

この行を変更すると、コードは希望どおりに動作します。