MCU&RCU

[essilor]

Does anyone know the exact rule to create RCU? I mean under what conditions do you need to create a RCU, even though one is already existing?

[Richard Tame]

There is no 'rule' per se. Multiple RCUs allow you to perform a different variety of pairing in your CA configuration. For instance if your primary array had 4 CU in use and your secondary array had 16 CU, it is unlikely a one-one relationship sould be suitable (as there would be insufficient LDEV in each CU).

Multiple RCUs allow you to distribute the pairs to various CUs.