By default, a cell contains a single core group. In this situation, during node federation, a node agent is created and automatically added to this core group. However, if the cell contains multiple core groups, specify the core group to which the node agent is assigned. If the cell to which you are adding a node agent contains multiple core groups, determine the core group to which you want this node agent to belong.
To add a newly created node agent to a specific core group:
addNode dmgr_host dmgr_port -coregroupname existing_core_group_name