The volumes you assign to the two replacement NEWCKPTn data sets need not be unique, although IBM® suggests that these two data sets reside on a separate volume from their primary data set counterparts. Both backup data sets can be specified on a single volume. This will generally provide sufficient protection from checkpoint data set loss; however, this configuration can cause some degree of performance degradation until the unavailable data set or volume is again available.

If the checkpoint data set resides on a Coupling facility structure, you can exercise some control over its placement through the use of preference and exclusion lists. For more information about how to specify these lists in your Coupling facility resource management (CFRM) policy, see z/OS MVS Setting Up a Sysplex and z/OS Communications Server: New Function Summary.