In DB2® pureScale® environments, the cf_transport_method configuration parameter controls what method is used for communication between DB2 members and the cluster caching facility (CF).
When cf_transport_method is set to RDMA, DB2 members must communicate with the CF by using remote direct memory access (RDMA). To use an RDMA protocol network, the hardware configurations that you must use are an InfiniBand network with the appropriate InfiniBand hardware installed or an Ethernet network that uses a RoCE adapter card.
When the cf_transport_method parameter is set to TCP, DB2 members communicate with the CF by using a TCP/IP protocol network.