Dynamic Allocation

If used, protection log and command log data sets for use in Adabas cluster environments are specified in the session startup JCL. Session initialization writes the log data set names to the parallel participant table (PPT) and ADARES uses dynamic allocation to access them.

The same is true of the Work data set: it is specified in the session startup JCL. Session initialization writes the Work data set name to the PPT and, in the event of an autorestart, a nucleus is able to access the Work data set of a peer nucleus using dynamic allocation.

Dynamic allocation is currently available only in cluster environments (when the NUCID is greater than zero). However, dynamic allocation is used by a noncluster nucleus to determine that the previous nucleus session was a cluster session and PLOGs or CLOGs remain to be copied.


JCL Considerations

Files that are eligible for dynamic allocation by another database must be cataloged, rather than being accessed using explicit UNIT and VOLSER keywords in the JCL. If JOBCAT or STEPCAT DD statements are used to define a catalog search structure, these statements must be used in a consistent way on all database startup jobs in the sysplex.