The documentation at

http://www.jgroups.org/manual/html/user-advanced.html#ForkChannelCreation

has the following example:

JChannel main_ch=new JChannel("/home/bela/udp.xml").name("A");
ForkChannel fork_ch=new ForkChannel(main_ch, "lock", "fork-ch4",
                                    new CENTRAL_LOCK(), new STATS());
fork_ch.connect("bla");
main_ch.connect("cluster");

This does not work as "fork_ch.connect" will throw an IllegalStateException because the main channel is not connected at that point.

But if the connects are reversed, messages for the fork channel may arrive before the fork channel is fully established and cause warnings like

Feb 20, 2020 6:15:37 PM org.jgroups.protocols.FORK$1 handleUnknownForkChannel
WARNING: marian-20309: fork-channel for id=fork-ch4 not found; discarding message

My application will send a message to every new member in the cluster on a specific fork channel (in ReceiverAdapter.viewAccepted). These message usually get lost. Is there an alternate pattern for that?

I can provide example code if required.