CFX-Pre automatically chooses whether the connection is direct (one-to-one) or not, based on whether the nodes are coincident and the selection of regions on side 1 and side 2. The tolerance used to determine if nodes match across the interface, Mesh Match Tolerance, can be set in CFX-Pre under Edit > Options > CFX-Pre > Mesh. The actual connection type chosen is reported by CFX-Pre when the CFX-Solver input file is written.

An automatic connection cannot be made when conditional connection control is used for the interface. In such a case, the only available mesh connection option is GGI. For details on conditional connection control, see Conditional Connection Control in the CFX-Pre User's Guide and Conditional Connections.