When a volume is entered into an IBM automated or manual tape library, the cartridge entry installation exit (CBRUXENT) is invoked to approve or deny an enter request and to set or verify the recording technology to be associated with a volume. If a volume TCDB record does not exist for the entry of a private MEDIA5, MEDIA6, MEDIA7 or MEDIA8 volume and there is no applicable recording technology being provided by the library's entry default data class, EFMT1 is passed to the exit; unknown is passed for a scratch volume.

If the exit returns with a recording technology for a MEDIA5, MEDIA6, MEDIA7, or MEDIA8 volume and it is not EFMT1 or EFMT2, the specification is considered invalid and the exit is disabled.

For a MEDIA9 or MEDIA10 volume, EFMT2 is passed to the exit as this is the only applicable recording technology for these media types; any other specification is considered invalid and the exit is disabled.

If a TCDB volume record exists and the volume's recording technology or media type is not supported on the system processing the volume, in an ATLDS, the volume is left in the library manager insert category to be processed by a system with appropriate support.

If CBRXLCS FUNC=MCE is used to enter a volume into an MTL and its existing TCDB record has EFMT2 recording technology or an unsupported media type (MEDIA9/MEDIA10) and the software does not support the recording technology and/or the media type, the request is failed with existing return code LCSFAIL (12) and existing reason code LCSFNSUP (310). If the CBRUXENT exit returns a recording technology or media type not supported in the MTL(up-level recording technology), the entry of the volume also fails.