If existing subsystems are physically moved within a library so that the subsystems are now associated with different subsystem numbers (for example, if the new subsystems are not added to the physical end of the library), perform the following steps to properly rebuild the new configuration:

1. Use HCD to delete all devices form the library or libraries involved (multiple libraries might be involved if the devices came from another library).
2. Activate the IODF that has all the devices from the libraries removed by activating from the ISPF HCD panels, or by entering the MVS ACTIVATE command on the z/OS console.
3. Use HCD to add all of the devices that are now in each affected library.
4. Activate the IODF that has all the devices defined by activating from the ISPF HCD panels, or by entering the MVS ACTIVATE command on the z/OS console.
5. Vary the devices online to MVS using the MVS VARY command.
6. Once again, activate the IODF containing all the tape devices to complete the configuration activity by activating from the ISPF HCD panels, or by entering the MVS ACTIVATE command on the z/OS console..
   Note: Steps 1–6 can be replaced with a system IPL using the IODF containing all of the library devices.