TCDB volume error status field and software error category in an automated tape library

When a hardware or software error is detected, the volume error status field in the tape configuration database (TCDB) is updated to reflect the error, and the volume may also be placed in the software error category in the library manager database. For a list of the possible error conditions, refer to the description of the errstat field in Displaying tape volume status.

More specifically, when a software error is detected for a scratch volume, this results in the volume being placed in the software error category in the library manager database. The setting of an error category prevents the volume from being selected for future nonspecific (scratch) mount requests. In addition, the error status field in the TCDB volume record is updated to reflect the software error condition.

Detecting software errors for private volumes

A software error detected for a private volume results in an update to the volume record in the TCDB with the appropriate error status; however, since private volumes are requested by volser and not by a category value, there is no need to place private volumes in the software error category.

Detecting hardware errors for volumes

When a hardware error is detected (for either scratch or private volumes), the error is tracked in the library manager database and in the TCDB. Since the library manager tracks hardware-related errors for volumes, there is no need to place the volume in the software error category.

Resetting the volume error status field

There are several ways to reset the volume error status field in the TCDB and, if applicable, move the volume out of the software error category:

General use programming interface CBRXLCS FUNC(CUA) can be used to change the volume’s use attribute from SCRATCH to PRIVATE, PRIVATE to SCRATCH, PRIVATE to PRIVATE, or SCRATCH to SCRATCH. See Change use attribute (CUA) for more information on how use this interface. If the only purpose of the CBRXLCS invocation is to reset the volume error status field, CBRXLCS FUNC(CUA) from SCRATCH to SCRATCH or PRIVATE to PRIVATE accomplishes this (it is not necessary to actually change the volume’s use attribute). Invoking CBRXLCS FUNC(CUA) will also move a volume out of the software error category.
The ISMF volume ALTER command or line operator can be used to update specific fields in the TCDB volume record, including the volume error status field. If no other changes to the volume are required, invoke ISMF ALTER to change the volume’s use attribute from PRIVATE to PRIVATE or SCRATCH to SCRATCH. Changing the volume’s use attribute from SCRATCH to PRIVATE or from PRIVATE to SCRATCH using ISMF ALTER also resets the volume’s error status field. Invoking ISMF ALTER against a volume record also moves a volume out of the software error category.
If a volume is ejected from the library where it resides and is reentered into the same library, or a different library, the volume error status field and software error category resets upon entry.
A successful audit of a volume resets a hardware error in the TCDB (such as misplaced volumes), but it does not clear a software error in the TCDB. Since hardware errors do not result in the volume’s category being changed, audit never alters the setting of a volume in the error category. If a scratch volume has a software error associated with it, a successful audit of the volume leaves the volume error condition set in the TCDB and leaves the volume in the error category.
Note: Also keep in mind that resetting a hardware error condition in the volume’s TCDB volume record does not clear the condition in the library manager database.
When DFSMSrmm is used, EDGUTIL with PARM='MEND(SMSTAPE)' can reset some error status values.

Displaying scratch volume counts

Whenever you use the DISPLAY SMS,LIBRARY command, the scratch volume counts that are displayed reflect the number of scratch volumes in the scratch media categories. If a scratch volume is in the software error category, it is not included in this count because it is not considered a usable scratch cartridge.

Displaying software error category count

Use the DISPLAY SMS,LIBRARY to display the number of scratch volumes currently in the software error category associated with a particular library. See Displaying library detail status for more information on this command.