I run the latest wildfly-9.0.0.Final. I have an environment with 2 host and 3 server per host. I noticed that there are a lot of warning like this
JGRP000012: discarded message from different cluster hq-cluster (our cluster is ee)
or this
JGRP000012: discarded message from different cluster ee (our cluster is hq-cluster)
With the same configuration in wildfly-8.2.0.Final I didn't noticed anything.
The strange thing is that warnings still appear even if I run only the domain controller with 1 server active. I think that the domain configuration (I used the default with full-ha profile) is missing something that can diffentiate jgroup channel but I don't know how