The documentation states the following instructions for avoiding NULSER errors for archive datasets.
If the default value of NULSER might no longer be appropriate at a site. If this is the case, select an actual volume serial number residing in the ATL or VTS that CA MICS uses when pre-allocation of a tape file is needed. Put an indefinite expiration date on the volume so that it is available for any new datasets in the future.
How do you handle this if the site does not allow never expiring expiration dates?
NULSER is not defined at some sites and this causes an error for the first execution of a job that builds a new history archive file.
If you cannot allocate a volume that never expires for the NULSER VOLSER, you will need to run the documented test (Add archive history file) against the volser each time you add a new GDG for archive datato ensure the value is still current.
If the job completes successfully, continue with the checklist. If it does not, you will need to follow the steps in the documentation to define a new volser as the NULSER volume.
Documentation on the NULLSER and NULLUNIT parameters can be found here.