Unlike a physical volume, a logical volume with data cannot be removed from a VTS by ejecting it from the library.
To remove a logical volume with data from a library, the volume must be physically exported from the library. For more information on the export process, see Exporting logical volumes from a 3494 VTS system.
When a logical volume is successfully exported from the library, the cartridge eject installation exit is notified and a notification call indicator (UXJEXPRT) is set in field UXJNCALL. The volume serial number of the stacked container volume on which the logical volume resides can be found in the stacked volume container field, UXJSTKVS. The installation or its tape management system then stores the container information for later use when the logical volume is imported back into a library. If the TCDB is shared across multiple systems but each system has its own tape management system database, the exit can return with RC=12 (IGNORE) if the exported volume is not known to this tape management system. This leaves the volume in the exported category to be processed by a system that "owns" that volume. If appropriate for the installation, the 32-character free form shelf location field in the TCDB volume record (located in the UXJSHLOC field of the cartridge eject installation exit parameter list) can also be used to store the container volume serial number. This would require that the volume record be kept after a logical volume is exported from the library.
If the volume record disposition returned from the exit indicates that the volume record should be kept and the shelf location returned from the exit is blank, LCS automatically stores the container volume serial number in the shelf location field of the volume record as STACKED=volser. This information can later be used in the volume-not-in-library installation exit (CBRUXVNL) to assist the installation and operator in importing a logical volume. LCS also stores this information if the exit is not to be invoked, the volume record disposition is KEEP, and the shelf location is blank.
This call to the installation exit is a notification call only because the export operation for the logical volume is near completion. This means that the logical volume has already been written to a stacked volume, which will soon be ready for removal. All cartridge eject parameter list fields that can be updated today when a physical volume is ejected from a library can be updated when a logical volume is exported from a library and are subject to the same validity checks. If the export then fails during completion processing, the library recovers by putting the exported volume back into the insert category. There is no failed eject notification call.