Re: [akka-user] Remote communication with ActorSytems started on single JVM

√iktor Ҡlang

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Jun 1, 2012, 8:15:51 AM6/1/12

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On Fri, Jun 1, 2012 at 2:10 PM, Yaroslav Klymko <t3h...@gmail.com> wrote:

Hi,

There is something inconvenient for me.
I'm using akka 2.0.1

object TestServer extends App {
val first = ActorSystem("first")
val last = ActorSystem("last")
last.actorOf(Props(new LogActor), "test")
first.actorOf(Props(new LogActor), "test")
}
class LogActor extends Actor {
protected def receive = {
case x => println(x)
}
}
object TestClient extends App {
ActorSystem().actorFor("akka://la...@127.0.0.1:2552/user/test") ! "last"
ActorSystem().actorFor("akka://fi...@127.0.0.1:2552/user/test") ! "first"
}

I have two systems (first and last) started on on JVM and trying to send messages to both of them from different JVM

However I can not send message to ActorSystem which was not initialized first.

I have the same bug on my phone! If I start talking before the callee picks up the phone they won't hear it :(

15:00:33.475 INFO [first-akka.actor.default-dispatcher-1] akka.event.slf4j.Slf4jEventHandler - Slf4jEventHandler started
15:00:33.974 INFO [first-akka.actor.default-dispatcher-1] akka.actor.ActorSystemImpl - REMOTE: RemoteServerStarted@akka://fi...@127.0.0.1:2552

15:00:34.199 INFO [last-akka.actor.default-dispatcher-2] akka.event.slf4j.Slf4jEventHandler - Slf4jEventHandler started
15:00:34.222 INFO [last-akka.actor.default-dispatcher-2] akka.actor.ActorSystemImpl - REMOTE: RemoteServerStarted@akka://la...@127.0.0.1:2552

15:00:47.508 INFO [first-akka.actor.default-dispatcher-3] akka.actor.ActorSystemImpl - REMOTE: RemoteClientStarted@akka://def...@127.0.0.1:2553
15:00:47.550 ERROR [first-akka.actor.default-dispatcher-5] NettyRemoteTransport(null) - dropping message last for non-local recipient akka://la...@127.0.0.1:2552/user/test at akka://fi...@127.0.0.1:2552 local is akka://fi...@127.0.0.1:2552

15:00:47.570 INFO [first-akka.actor.default-dispatcher-5] akka.actor.ActorSystemImpl - REMOTE: RemoteClientStarted@akka://def...@127.0.0.1:2553
15:00:47.576 INFO [first-akka.actor.default-dispatcher-5] akka.actor.ActorSystemImpl - REMOTE: RemoteClientShutdown@akka://def...@127.0.0.1:2553
first

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Viktor Klang

Akka Tech Lead

Typesafe - The software stack for applications that scale

Twitter: @viktorklang

Jonas Bonér

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Jun 1, 2012, 8:24:40 AM6/1/12

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On Fri, Jun 1, 2012 at 2:15 PM, √iktor Ҡlang <viktor...@gmail.com> wrote:
>
>
> On Fri, Jun 1, 2012 at 2:10 PM, Yaroslav Klymko <t3h...@gmail.com> wrote:
>>
>> Hi,
>>
>> There is something inconvenient for me.
>> I'm using akka 2.0.1
>>
>>>
>>> object TestServer extends App {
>>> val first = ActorSystem("first")
>>> val last = ActorSystem("last")
>>> last.actorOf(Props(new LogActor), "test")
>>> first.actorOf(Props(new LogActor), "test")
>>> }
>>> class LogActor extends Actor {
>>> protected def receive = {
>>> case x => println(x)
>>> }
>>> }
>>> object TestClient extends App {
>>> ActorSystem().actorFor("akka://la...@127.0.0.1:2552/user/test") ! "last"
>>> ActorSystem().actorFor("akka://fi...@127.0.0.1:2552/user/test") !
>>> "first"
>>> }
>>
>>
>> I have two systems (first and last) started on on JVM and trying to send
>> messages to both of them from different JVM
>> However I can not send message to ActorSystem which was not initialized
>> first.
>
>
> I have the same bug on my phone! If I start talking before the callee picks
> up the phone they won't hear it :(

My wife has the same problem. If she starts speaking to me while I'm
hacking, before I get a chance to fully switch context, then I won't
hear anything she is saying. Drives her nuts, but can be quite
convenient sometimes.

Jonas Bonér
CTO

Typesafe - The software stack for applications that scale

Phone: +46 733 777 123
Twitter: @jboner

√iktor Ҡlang

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Jun 1, 2012, 8:27:48 AM6/1/12

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Haha, I get tons of crap from Sandra for that. Glad to hear it's not just me!

√iktor Ҡlang

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Jun 1, 2012, 8:33:53 AM6/1/12

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You can't use the same host and port for more than one ActorSystem

Cheers,

√

On Fri, Jun 1, 2012 at 2:31 PM, Yaroslav Klymko <t3h...@gmail.com> wrote:

Haha very funny :)

However,
I meant that the message will go only to second system and will be dropped from the first one...

So whenever I have more then one ActorSystem on the single JVM I can't reach remotely one of them....
Could you please read logs I'v attached ?

Best regards.

>>> RemoteServerStarted@akka://firs...@127.0.0.1:2552

>>> 15:00:34.199 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.event.slf4j.Slf4jEventHandler - Slf4jEventHandler started
>>> 15:00:34.222 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.actor.ActorSystemImpl - REMOTE:

>>> RemoteServerStarted@akka://last...@127.0.0.1:2552

>>> 15:00:47.508 INFO [first-akka.actor.default-dispatcher-3]
>>> akka.actor.ActorSystemImpl - REMOTE:

>>> RemoteClientStarted@akka://defau...@127.0.0.1:2553

>>> 15:00:47.550 ERROR [first-akka.actor.default-dispatcher-5]
>>> NettyRemoteTransport(null) - dropping message last for non-local recipient
>>> akka://la...@127.0.0.1:2552/user/test at akka://fi...@127.0.0.1:2552 local is
>>> akka://fi...@127.0.0.1:2552
>>> 15:00:47.570 INFO [first-akka.actor.default-dispatcher-5]
>>> akka.actor.ActorSystemImpl - REMOTE:

>>> RemoteClientStarted@akka://defau...@127.0.0.1:2553

>>> 15:00:47.576 INFO [first-akka.actor.default-dispatcher-5]
>>> akka.actor.ActorSystemImpl - REMOTE:

>>> RemoteClientShutdown@akka://defa...@127.0.0.1:2553

>>> first
>>>
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "Akka User List" group.
>> To view this discussion on the web visit
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>> To unsubscribe from this group, send email to

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>> For more options, visit this group at
>> http://groups.google.com/group/akka-user?hl=en.
>
>
>
>
> --
> Viktor Klang
>
> Akka Tech Lead
> Typesafe - The software stack for applications that scale
>
> Twitter: @viktorklang
>
> --
> You received this message because you are subscribed to the Google Groups
> "Akka User List" group.
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> For more options, visit this group at
> http://groups.google.com/group/akka-user?hl=en.

--
Jonas Bonér
CTO
Typesafe - The software stack for applications that scale
Phone: +46 733 777 123
Twitter: @jboner

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Derek Wyatt

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Jun 1, 2012, 8:37:32 AM6/1/12

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On 2012-06-01, at 8:33 AM, √iktor Ҡlang wrote:

You can't use the same host and port for more than one ActorSystem

If that's the case then I think there's a potential ticket here, no?

>>> RemoteServerStarted@akka://firs...@127.0.0.1:2552
>>> 15:00:34.199 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.event.slf4j.Slf4jEventHandler - Slf4jEventHandler started
>>> 15:00:34.222 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.actor.ActorSystemImpl - REMOTE:
>>> RemoteServerStarted@akka://last...@127.0.0.1:2552
>>> 15:00:47.508 INFO [first-akka.actor.default-dispatcher-3]

How is it possible that "RemoteServerStarted @ akka://la...@127.0.0.1:2552" appears? Why wouldn't it be "RemoteServerNOTStarted due to 'port already in use' error"?

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√iktor Ҡlang

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Jun 1, 2012, 8:45:34 AM6/1/12

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On Fri, Jun 1, 2012 at 2:37 PM, Derek Wyatt <de...@derekwyatt.org> wrote:

On 2012-06-01, at 8:33 AM, √iktor Ҡlang wrote:

You can't use the same host and port for more than one ActorSystem

If that's the case then I think there's a potential ticket here, no?

There is already a ticket, but IMHO it doesn't make sense. What would it mean? When would you shut the port down? It's global state, so how do you test it?

>>> RemoteServerStarted@akka://firs...@127.0.0.1:2552
>>> 15:00:34.199 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.event.slf4j.Slf4jEventHandler - Slf4jEventHandler started
>>> 15:00:34.222 INFO [last-akka.actor.default-dispatcher-2]
>>> akka.actor.ActorSystemImpl - REMOTE:
>>> RemoteServerStarted@akka://last...@127.0.0.1:2552
>>> 15:00:47.508 INFO [first-akka.actor.default-dispatcher-3]

How is it possible that "RemoteServerStarted @ akka://la...@127.0.0.1:2552" appears? Why wouldn't it be "RemoteServerNOTStarted due to 'port already in use' error"?

Also, I do not know if he's running in daemonic mode or not, so I don't know if his TestServer is exiting after init or not.

Cheers,

√

Derek Wyatt

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Jun 1, 2012, 8:48:50 AM6/1/12

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There is a ton of historical precedent here. The "port already in use" error is a well known error condition as I'm sure you know. I get what you're saying but might you be getting buried in the corner cases?

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√iktor Ҡlang

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Jun 1, 2012, 8:58:05 AM6/1/12

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On Fri, Jun 1, 2012 at 2:48 PM, Derek Wyatt <de...@derekwyatt.org> wrote:

There is a ton of historical precedent here. The "port already in use" error is a well known error condition as I'm sure you know. I get what you're saying but might you be getting buried in the corner cases?

Well.... this is what I get:

scala> val as = akka.actor.ActorSystem("foo", parseString("""

| akka {

| actor.provider = "akka.remote.RemoteActorRefProvider"

| remote.netty {

| hostname = localhost

| port = 12345

| }

| }"""))

[INFO] [06/01/2012 14:56:55.818] [run-main] [ActorSystem(foo)] RemoteServerStarted@akka://foo@localhost:12345

as: akka.actor.ActorSystem = akka://foo

scala> val as = akka.actor.ActorSystem("bar", parseString("""

| akka {

| actor.provider = "akka.remote.RemoteActorRefProvider"

| remote.netty {

| hostname = localhost

| port = 12345

| }

| }"""))

org.jboss.netty.channel.ChannelException: Failed to bind to: localhost/127.0.0.1:12345

at org.jboss.netty.bootstrap.ServerBootstrap.bind(ServerBootstrap.java:298)

at akka.remote.netty.NettyRemoteServer.start(Server.scala:55)

at akka.remote.netty.NettyRemoteTransport.start(NettyRemoteSupport.scala:161)

at akka.remote.RemoteActorRefProvider.init(RemoteActorRefProvider.scala:83)

at akka.actor.ActorSystemImpl._start(ActorSystem.scala:576)

at akka.actor.ActorSystemImpl.start(ActorSystem.scala:583)

at akka.actor.ActorSystem$.apply(ActorSystem.scala:99)

at akka.actor.ActorSystem$.apply(ActorSystem.scala:94)

at .<init>(<console>:8)

at .<clinit>(<console>)

at .<init>(<console>:11)

at .<clinit>(<console>)

at $print(<console>)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

at java.lang.reflect.Method.invoke(Method.java:597)

at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)

at scala.tools.nsc.interpreter.IMain$Request.loadAndRun(IMain.scala:914)

at scala.tools.nsc.interpreter.IMain.loadAndRunReq$1(IMain.scala:546)

at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:577)

at scala.tools.nsc.interpreter.IMain.interpret(IMain.scala:543)

at scala.tools.nsc.interpreter.ILoop.reallyInterpret$1(ILoop.scala:694)