SYS1.UADS and SYS1.BRODCAST

The default SYSTEMS exclusion RNL includes entries for SYS1.UADS and SYS1.BRODCAST, causing them to be local resources while you decide whether your installation wants them to be global resources. To make this decision, your installation must investigate and measure:

Resource requirements (that is, the resources required to merge multiple versions of the two data sets into a single version of each and test the new versions)
Performance implications (that is, the performance of one version of each data set accessed by all users in contrast to multiple versions of the same data sets each accessed by a subset of those users)

There are, however, significant advantages to treating SYS1.UADS and SYS1.BRODCAST as global resources:

Your installation has only two data sets to maintain, rather than two data sets for each TSO/E system in the complex.
A user can logon from any system in the complex, allowing a better workload balance.
For foreground-initiated background jobs, a user who specifies NOTIFY will always receive the job-ended message regardless of which system in the complex processed the job.

To cause global resource serialization to treat SYS1.UADS and SYS1.BRODCAST as global resources, you must:

Merge all existing versions of SYS1.UADS and SYS1.BRODCAST into a single version of each data set.
Modify the default RNLs:
1. Delete the entries for SYS1.UADS and SYS1.BRODCAST from the SYSTEMS exclusion RNL.
2. Add SYSIKJUA as a generic qname entry in the SYSTEM inclusion RNL to make SYS1.UADS a global resource.
3. Add SYSIKJBC as a generic qname entry in the SYSTEM inclusion RNL to make SYS1.BRODCAST a global resource.

Note: This procedure prohibits you from logging on more than once in a SYSPLEX if the scope is converted to SYSTEMS.

Related information appears in z/OS TSO/E Customization. Some of the information is repeated here for your convenience.