Mainframe, MVS and zOS Discussion

Hello,

Can anybody please tell me the maximum limit for a GDG generation? From the manuals, it is 255. However, when I create a new GDG with NOEMPTY, NOSCRATCH option it created more than 258 generations without deleting the previous generations. And all the generations are catalogued. So what is correct? Please help.

The limit of generations that can be managed for a GDG is 255 -- period. HOWEVER, depending upon the options used when the GDG was built, there may APPEAR to be more than 255 generations in the catalog. This is because the options (such as NOEMPTY NOSCRATCH) determine whether or not to delete the rolled-off generations and remove them from the catalog. If they are not removed from the catalog and deleted, they will still be on the system and show up on data set listings -- but they will NOT be managed as part of the GDG.

Any generation after 255 (provided the limit is set to that) will not be chronologically attached to the GDG Base, as Robert has said. Or in simple words - they are just another data-set on with a specific naming convention.

Thanks Robert and Anuj. Got it.

You're welcome!