ALTER BCS-BACK-POINTERS

Use the ALTER BCS-BACK-POINTERS command to quickly and easily change the BCS back-pointer value in one or more VVDS records.

The primary function of the ALTER BCS-BACK-POINTERS command is to change the BCS back-pointer fields. After performing this function on each volume, the command processor checks if the old BCS owns any data sets on the volume. If it does not, the BCS name is removed from the VVCR (and any VVCN) records in the VVDS of that volume. This effectively severs the BCS and this VVDS from a valid ICF catalog relationship. If the new BCS name is not already contained in the VVCR of each volume processed, it is added. This effectively creates a valid ICF catalog relationship for the BCS and VVDS.

Syntax

Read syntax diagramSkip visual syntax diagramALTERBcs-Back-PointersINClude-Storagegroup(,stgrpstgrpmask)INClude-VOLser(,volservolsermask)INClude-Storagegroup(,stgrpstgrpmask)INClude-VOLser(,volservolsermask)New-BCS( bcs)Old-BCS(bcsALL)SIMulateINClude-Dsn(,dsndsnmask)EXClude-Dsn(,dsndsnmask)EXClude-Storagegroup(,stgrpstgrpmask)EXClude-VOLser(,volservolsermask)PRinT(NONE)PRinT(NONEDATAKEY)ReMoVe1
Notes:
  • 1 If you specify REMOVE, you cannot specify NEW-BCS, INCLUDE-DSN, EXCLUDE-DSN, or PRINT(KEY).

ALTER BCS-BACK-POINTERS Command Syntax

Keywords

INCLUDE-STORAGEGROUP
specifies one or more specific or masked SMS storage groups of volumes to process.
INCLUDE-VOLSER
specifies one or more specific or masked volume serial numbers of the volumes on which VVDSs are to be processed. All selected volsers must be for volumes that are currently online to the system where the ALTER command is run.
NEW-BCS
specifies the new fully qualified data set name of the BCS that replaces all occurrences of the OLD-BCS name.
OLD-BCS
indicates the BCS name to search for and replace with the NEW-BCS name.
  • bcs—the fully qualified data set name of the BCS.
  • ALL—specifies that all un-referenced BCS names in the selected VVDSs are to be removed.

    ALL can only be specified when the REMOVE keyword is also specified. When specified, the command processor scans the entire VVDS, comparing the BCS names in the VVCR/VVCN to the BCS back-pointers in each VVR/NVR, and when a BCS name is not found to exist in any VVR/NVR, it is then removed from the VVCR/VVCN.

SIMULATE
indicates that you want to test the command without actually performing it.
INCLUDE-DSN
specifies one or more specific or masked data set names whose VVR/NVR records are searched for in the VVDSs from the selected volume serial number list.
EXCLUDE-DSN
specifies one or more specific or masked data set names to exclude from processing.
EXCLUDE-STORAGEGROUP
specifies one or more specific or masked SMS storage groups of volumes to exclude from processing.
EXCLUDE-VOLSER
specifies one or more specific or masked volume serial numbers to exclude from processing.
PRINT
specifies the level of printing to SYSPRINT that takes place during processing.
  • NONE—do not print anything. This is the default.
  • DATA—print the complete record, including key and data, from the VVDS being altered.
  • KEY—print only the key from the VVDS record being altered. Because the VVDS is structurally an ESDS, its records do not have keys so the component name of the data set record is printed.
REMOVE
deletes pointers in a VVDS that are pointing to non-existent catalogs. For each selected volume, the relationship with the VVDS and each BCS is validated. If the VVDS indicates a relationship with a BCS, and the BCS either no longer exists or does not contain the corresponding SYS1.VVDS.Vvolser entry, and no VVR or NVR records in that VVDS have a back-pointer to that BCS, then the name of that BCS is unregistered from the VVDS. Otherwise, the REMOVE is not performed. OLD-BCS is not necessary with REMOVE, but when specified it must be OLD-BCS(ALL).
If you specify REMOVE, you cannot specify NEW-BCS, INCLUDE-DSN, or EXCLUDE-DSN. If PRINT is specified, it will be ignored.

Usage notes

  • When updating VVDS records for a volume that contains system page (or swap) data sets, you must absolutely ensure that none of the paging data sets currently in use by an active system will be affected. If these VVRs become updated, active systems using those paging data sets can crash with a delayed 02E wait-state when an ongoing 10-minute system timer expires.