Figure 1 is an overview of the conversion environment for migration processing. The following steps are recommended for converting to an automated tape library:

1. Fill the library with existing ML2 and scratch tapes. The LIST ML2 command can be used to identify ML2 tapes that are outside the library. For more information about the LIST command, see z/OS DFSMShsm Storage Administration.
2. Set up the ACS routines to map all new migrations to the library. In order to create original and alternate tapes in the same or different locations, ACS routines must filter on both data set names. For information on how to set up ACS routines, refer to z/OS DFSMS Implementing System-Managed Storage.
3. All mounts for recalls from library-resident tapes will be automated. If a DFSMShsm migration tape has been ejected from the library, the ARCTEEXT installation exit can be used to enable the capability to dynamically insert the tape whenever it is needed.
4. Eject alternate volumes if they are not already outside the library. These tape volumes may have been created as a result of duplex or TAPECOPY processing. You can identify them by using the LIST TTOC SELECT (ML2 FULL LIB(ALT)) command.
   Note: If your remote locations are creating tapes simultaneously, you may even have an entirely different set of tape management policies.

Figure 1. Overview of Implementing Migration in an Automated Tape Library