Since Teiid is installed in JBoss AS, there is no additional configuration needed beyond what was performed when Teiid is setup in Domain Mode. See the Domain Mode section in the Teiid Installation Guide. Just make sure that you installed Teiid in every JBoss AS node and started all JBoss AS instances in the Domain mode that to be a part of the cluster.
Typically users create clusters to improve the performance of the system through:
Load Balancing: Take look at the Client Developer's Guide on how to use load balancing between multiple nodes.
Fail Over: Take look at the Client Developer's Guide on how to use fail over between multiple nodes.
Distributed Caching: This is automatically done for you once you configure it as specified above.
Event distribution: metadata and data modifications will be distributed to all cluster members.
In the Domain mode, the only way a user can deploy any artifacts is using either CLI or using the Admin API or Admin Shell. Copying VDB directly into the "deployments" directory is not supported.