Using the SETSYS TAPEMIGRATION parameter

You can specify that DFSMShsm use only tape volumes for ML2 volumes.

Example: You can add the following SETSYS TAPEMIGRATION command to the ARCCMDxx member in each DFSMShsm host:

SETSYS TAPEMIGRATION(ML2TAPE(TAPE(ACL)) RECONNECT(ALL))

The TAPEMIGRATION parameter of the SETSYS command specifies how migration to tape occurs. The ML2TAPE subparameter specifies that migration occurs from ML1 to ML2 tape. The TAPE(ACL) option of the ML2TAPE subparameter limits the kind of tape unit that is selected to the kind of unit that is specified. This example specifies that only units that are identified by the esoteric name of ACL can be used as output tape units for ML2 volumes.

The RECONNECT parameter of the SETSYS TAPEMIGRATION command controls whether DFSMShsm attempts to reconnect a data set that is recalled from a single ML2 tape to that migration copy when the data set is next migrated.

The ALL keyword of the fast subsequent migration RECONNECT parameter specifies that you want all eligible data sets to reconnect to their ML2 tapes. You want this to occur even if the data sets would otherwise be migrated to ML1.

Note: Only data sets that are directed to ML1 by the FORCML1 parameter (on the ARCHMIG macro) are excluded from reconnection.

Alternative subparameters that have meaning to SMS-managed data sets are NONE and NONE(ROUTETOTAPE).

The NONE subparameter specifies that ML2 volumes are DASD. NONE(ROUTETOTAPE(unittype)) specifies that although ML2 volumes are DASD, any management class with a value of 0 in the LEVEL 1 DAYS NON-USAGE attribute causes data sets to migrate directly to tape of the kind specified by unittype. The unittype subparameter restricts the kind of unit for the ML2 tape unit.

If you specify TAPEMIGRATION(NONE) or TAPEMIGRATION(NONE(ROUTETOTAPE(unittype))), you can define key ranges to be stored on different DASD ML2 volumes. The MIGRATIONLEVEL2 parameter of the DEFINE command specifies the key ranges for DASD ML2 volumes.

Guideline: If you do not intend to use tape, do not specify TAPEMIGRATION. If you do, an offline control data set is required.

With SMS, both DASD and tape can be used together by specifying the NONE or (NONE(ROUTETOTAPE) subparameters of the TAPEMIGRATION parameter and specifying LEVEL 1 DAYS NON-USAGE = 0 in some management classes. Under those specifications, level 1 to level 2 migration is to DASD but migration from DFSMShsm-managed volumes is to tape for data sets in the appropriate management classes.

When migrating SMS volumes and both PRIMARY DAYS NON-USAGE and LEVEL 1 DAYS NON-USAGE have been satisfied in an ML2 tape environment, the SMS data sets are moved directly to ML2 tape. In an ML2 DASD environment, the target is ML1 DASD unless LEVEL 1 DAYS NON-USAGE is 0.

Using the SETSYS TAPEMIGRATION parameter

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