SMS control data sets can be either SMS-managed or non-SMS-managed. Initially, you should ensure that your control data sets have a volume count of 1. The volume count can be explicitly specified, implied by the number of volume serials provided, or derived from the data class assigned to the data set (for more information, see z/OS DFSMSdfp Storage Administration). If you give an SMS control data set a volume count that is greater than the number of volumes on which the data set actually resides, you might receive messages IEF244I and IEF489I when you attempt to activate it.

If you have a multivolume SCDS that you are activating into a single volume ACDS, you might receive an error because the ACDS is not large enough and volumes cannot be dynamically added to it. To bypass this problem, you need to create a new multivolume ACDS and then activate the ACDS and SCDS simultaneously using the SETSMS command. See Changing storage management subsystem parameters for further information on this command.

If your SMS complex includes more than 16 systems, be sure that the ACDS and COMMDS are accessible to every system in the complex. Define your control data sets on volumes which are capable of being attached to more than 16 systems, such as IBM RAMAC™ Virtual Array volumes.