If the EXPIREDDATASETS(SCRATCH) parameter is specified in the SETSYS
command, DFSMShsm deletes any non-VSAM data set whose VTOC entry shows
that the data set has passed its expiration date and any VSAM data
set whose catalog entry shows that the data set has passed its expiration
date. The management class expiration attributes control the expiration
of non-VSAM data sets that do not have a valid expiration date in
their data set VTOC and VSAM data sets that do not have a valid expiration
date in their base cluster catalog entry.
Note: For multivolume
non-VSAM data sets, DFSMShsm looks at the VTOC of the first volume.
If concurrent copy was used to back up the data set and a system
failure or cancel of DFSMShsm occurred after the concurrent copy session
was established, then the data-set-changed indicator can be off even
though the data set was not successfully backed up. This can result
in the data set prematurely meeting the expiration criteria.
DFSMShsm provides a patch byte that enables users to override the
requirement that an SMS-managed data set have a backup copy before
it is expired. For more information about this patch, see the topic
about tuning DFSMShsm in z/OS DFSMShsm Implementation and Customization Guide.
DFSMShsm deletes rolled-off generation data sets that meet either
of the following conditions, regardless of the EXPIREDDATASETS parameter
of the SETSYS command.
- It is associated with a management class that has the attribute
ROLLED-OFF GDS ACTION=MIGRATE and both of the following apply:
- It does not have an expiration date in the data set VTOC entry.
- It has passed the date and time limit specified by the EXPIRE
AFTER DAYS NON-USAGE and EXPIRE AFTER DATE/DAYS attributes in the
management class.
- It is associated with a management class with the attribute ROLLED-OFF
GDS ACTION = EXPIRE and it has no expiration date in the data set
VTOC entry.
Note: DFSMShsm deletes active generation data
sets in the same way it deletes non-GDS data sets.