Page 2 of the Management Class Define panel contains the management class migration and GDG management attributes. SCDS Name and Management Class Name are output fields that contain the SCDS and management class names you specified in the Management Class Application Selection panel.
To define a management class, you must specify values for the Partial Release and Command or Auto Migrate attributes. If you specify BOTH for the Command or Auto Migrate attribute, then Primary Days Non-usage and Level 1 Days Non-usage become required fields. If you specify NONE for the Command or Auto Migrate attribute, the expiration attributes specified on page 1 of this panel still apply. The other fields on this panel are optional.
For more information on partial release, refer to z/OS DFSMS Using Data Sets.
A nonzero number for Level 1 Days Non-usage indicates the number of days that must elapse since the last reference on level 0 before a data set on ML1 can migrate from level 1 to level 2. The default is 60.
The Command or Auto Migrate attribute allows you to specify if a data set is eligible to be migrated by BOTH command and automatic processing, by command alone, or not at all (NONE).
If you do not want to migrate data sets that belong to a particular management class, specify NONE in the Command or Auto Migrate field. The data sets remain on primary storage until they expire. If you want data sets to be eligible for migration directly from level 0 storage to level 2 tape, specify 0 in the Level 1 Days Non-usage field. Otherwise, the data sets must first migrate to level 1 (the days spent on level 0 count toward the eligibility of moving to level 2).
The # GDG Elements on Primary attribute indicates how many of the most recent generations of a GDG use the normal Primary Days Non-usage attribute for migration criteria. Generations that are over this limit are eligible for early migration during the next processing of primary space management. The inactive age is irrelevant for these 'over the limit' GDSs and they are given a higher selection priority so they are likely to be migrated if space is needed to meet volume thresholds.
To specify that old generations are to have priority for migration and to specify how many generations are to have standard priority, you can specify the # GDG Elements on Primary attribute. When you specify this attribute, all non-rolled-off generations of each GDG that exceed the number you specify are given priority for early migration. If you specify 0 for this attribute, all generations of the GDGs are given priority for early migration. Those data sets made eligible for early migration do not have to satisfy the Primary Days Non-usage criteria.
All generations that meet the Primary Days Non-usage criteria are eligible to migrate. # GDG Elements on Primary enables you to accelerate migration of older generations while Primary Days Non-usage enables you to specify migration criteria of younger generations separately.
The Rolled-off GDS Action value indicates whether to expire rolled-off GDSs or to make them eligible for migration. If you specify MIGRATE, management class expiration attributes are applied to the data set to determine if the data set should be deleted; if not, the data set is eligible for migration. If you specify EXPIRE, the rolled-off GDS is deleted unless an explicit expiration date is in the DSCB. In this case, the rolled off GDS becomes a non-GDG data set and migrates according to non-GDG migration attributes.
Both the # GDG Elements on Primary and the Rolled-off GDS Action attributes are optional and have default values of blank. If left blank, no special treatment results from the data set being a GDS or a rolled-off GDS. That is, other management class attributes is used to process the data set.
During automatic primary space management, GDSs that have been determined as eligible for migration are migrated in the following priority order:
After specifying the migration attributes, issue the DOWN command to specify the backup attributes on the next page of the Management Class Define panel.