Specifying the first qualifier for names of migrated data sets

When DFSMShsm migrates a data set, it leaves the original data set name in the catalog. For use in its own records, DFSMShsm generates its own name for the data set. The form of the data set name that DFSMShsm generates is: 
prefix.HMIG.Tssmmhh.user1.user2.Xyddd
If patch-enabled, the following dataset name will be generated:
prefix.HMIG.Tcccchh.user1.user2.Xyddd

For more information, refer to "Changing DFSMShsm backup and migration generated dataset names to reduce contention for similar names and eliminating a possible performance degradation" in the "Tuning DFSMShsm" chapter of z/OS DFSMShsm Implementation and Customization Guide.

The MIGRATEPREFIX parameter of the SETSYS command specifies the prefix (high-level qualifier) of the generated name. If you do not specify a migrate prefix, DFSMShsm uses the UID that you specified in the startup procedure.

The migrate prefix is used in the ACS filters that prevent DFSMShsm-owned data sets from being allocated on SMS-managed volumes. In addition, the use of the prefix allows you to use RACF® generic profile protection for all your migration copies.

Example: You can add the following command to the ARCCMDxx member in each DFSMShsm host: 
SETSYS MIGRATEPREFIX(HSM)

Related reading

Parent topic: Tasks for automatic space management