Multicast problem :(

[tricky]

Hi all,

I have a question. I need to create multicast socket but on more then
one interface. I try to do this but unfortunetly it is setup only on one
interface ?
Do a need different ip (group ) per each interface or maybe port or maybe
it's impossible ?

port and ip is the same per each interface
During iterations setInterface() is invoked

public void setInterface(NetworkInterface i){
try {
logger.info("MulticastAnnouncer");

this.address = InetAddress.getByName(defaultIP);
this.socket = new MulticastSocket(port);
this.socket.setNetworkInterface(i);
this.socket.joinGroup(this.address);

 

[Esmond Pitt]

Do a need different ip (group ) per each interface

Yes

 

[tricky]

Yes

Unfortunetly it doesn't work only default interface is used


private static final String defaultIP = "239.0.2.10"; <-this is changed
depended on interface number

public void setInterface(NetworkInterface i){
try {
logger.info("MulticastAnnounce setting interface");

this.address = InetAddress.getByName(defaultIP);
this.socket = new MulticastSocket(port);
this.socket.setNetworkInterface(i);
this.socket.joinGroup(this.address);

logger.info("MulticastSocket Annoucer success");

this.socket = socket;

}catch(Exception e){
logger.error("Cannot set network Interface:"+e.toString());

}

 

[Esmond Pitt]

setInterface() is really only useful for outbound traffic. You need to
use the version of join() where you specify the NetworkInterface, in a
loop, so that you join the group via all available NICs.

 

[tricky]

It works under windows but not under linux