Akka-remote over the Internet

Question

I'm writing distributed BBS software using Akka 2.2.3 as remote message passing in Scala.

Then, I've found some problem in networking over the Internet through NAT: Akka doesn't recognize external IP address, AFAIK because it uses socket.bind.

Next, I thought that I can specify 0.0.0.0 as akka.remote.netty.tcp.hostname in order to adopt all interfaces and addresses to listen connections from the Internet side.

Here is the problem -- Akka uses 0.0.0.0 as its own IP address, and generates ActorRef like this: akka.tcp://system@0.0.0.0/user/foo.

Other nodes cannot refer the node using this ActorRef over the Internet. What should I do for connecting nodes over the Internet? Can't I use Akka over NAT?

Answer 1

Akka remoting does not support NAT, which is intentional since its purpose is just to enable clustering (i. e. symmetrical communication between a tightly controlled set of nodes). There are several protocols that have been devised for Internet-wide use, e. g. HTTP/REST (see Spray which is becoming Akka HTTP) or bare TCP using Akka IO.