Choosing the z/OS base and optional features
Rule: Because the z/OS® base elements and optional features are integrated into a single package with compatible service levels, you must install, with few exceptions, the entire z/OS product.
The exceptions are:
- Elements and features that are already installed do not have to be reinstalled if both of the following are true: (1) you use the CBPDO installation method to migrate to the current z/OS release and (2) an element or feature has not changed (its FMID did not change), or an element or feature is nonexclusive and you've already installed its functionally-equivalent separate product version. To find out which elements and features have changed in the current release, see Table 1.
- Unpriced features that you did not order do not have to be installed.
- JES2 does not have to be installed if you are a JES3 customer. Starting with V2R1, the staged migration path with old level of JES2 is no longer supported.
- JES3 does not have to be installed if you are a JES2 customer. Starting with V2R1, the staged migration path with old level of JES3 is no longer supported.
Failure to install the entire z/OS product, except for the described exceptions, could result in an unserviceable system until you install the entire product.
You can use the Planning and Migration Assistant (part of SMP/E) to help you determine what software is already on a system from which you are migrating.