Ejecting a tape cartridge from a tape library

Ejecting a cartridge from a tape library breaks the connection between the cartridge and the library in which it resided. Cartridges may need to be moved to a different location and must therefore be ejected from the library in which they currently reside so they may be put into a library at the new location. Once the cartridges are ejected from the library in which they reside, they are no longer associated with that library and are not eligible to be mounted in the library without going through the cartridge entry process.

In the automated tape library environment, there is currently a limit on the number of eject requests that device services can have queued across all libraries from a single system. This queue limit is currently set at 1600. For this limit to be as transparent as possible, OAM will not send more than 100 eject requests to a single library from a single system. If OAM receives more than 100 eject requests for a given library, it will wait until an eject request completes before sending another request to that library. However, if the OAM address space is stopped or restarted with an SCDS activation, rather than purging the remaining eject requests, OAM will try and send down as many of the remaining eject requests as it can before reaching the device services queue limit of 1600. Additionally, there is a Peer-to-Peer VTS system limitation. This library will only accept up to 1000 eject requests across all connected systems.

Recommendation: Given these limitations (and potential storage constraints when processing thousands of outstanding eject requests), limit the number of outstanding eject requests at any given time to no more than a couple thousand per system. Then, as the outstanding eject requests complete, more can be initiated.

Cartridges can be ejected from a tape library in several ways, as shown in Table 1:

Table 1. Methods for ejecting cartridges from a tape library
Eject request invoked by	Action taken to cause eject	Associated procedure
OAM	Ejects cartridge automatically following an unsuccessful cartridge entry attempt.	N/A
Operator	Ejects cartridge using the LIBRARY EJECT command.	Ejecting a specific Tape Volume
Storage administrator	Specifies an EJECT line operator next to a volume serial number on an ISMF Mountable Tape Volume List panel.	Ejecting a volume from a tape library
Application program	Issues the CBRXLCS macro with the EJECT function.	Ejecting a tape cartridge

Before a cartridge can be ejected from a tape library, the cartridge eject installation exit (CBRUXEJC) is invoked to approve or deny the eject request. See Cartridge eject installation exit (CBRUXEJC) for more information.

Rule: OAM does not support the manual removal of volumes from a 3494 tape library for the purpose of ejecting them. The volumes that are manually ejected from a library are still library-resident in the TCDB, causing an out-of-synchronization condition with the library manager database. Volumes must be ejected following the methods outlined in Table 1.

When OAM ejects a tape volume residing in a manual tape library, no automated movement of the cartridge takes place. It is up to the operator to physically remove the tape cartridge from the storage racks associated with the manual tape library.

After the eject request completes, OAM notifies the invoker of the eject request of its success or failure and the volume record in the TCDB is updated or deleted.

For information concerning exporting or removing a logical tape volume from a VTS, see Exporting logical volumes from a 3494 VTS system and Ejecting a logical Volume from a VTS.