Does the Prizm look like a control unit to the channel? How is Prizm configured in HCD/IOCDS?
Prizm looks like a FICON Multi-LCU Control Unit to the channel; however, Prizm is not defined as a device in HCD/IOCDS. The actual devices attached through Prizm are configured in HCD/IOCDS with unique CUADD’s. Best practice is to use the two digit FICON CUADD using the left digit as the Prizm port and the right digit as the normal ESCON CUADD value. For devices capable of direct attachment via ESCON and FICON channels, they are defined as the actual devices. Devices that do not have a FICON attachment capability have their CNTLUNIT TYPE set to NOCHECK in HCD/IOCDS.