When creating a new server instance or a new cluster, either:
Reference an existing configuration. No new configuration is added.
Make a copy of an existing configuration. A new configuration is added when the server instance or cluster is added.
By default, new clusters or instances are created with configurations copied from the default-config configuration. To copy from a different configuration, specify it when creating a new instance or cluster.
For more information, see:
When you create a clustered configuration, Application Server creates a cluster configuration directory on the domain administration server at domain-root/domain-dir/config/cluster-config. This directory is used to synchronize configurations for all instances in the cluster.