Abstract: Users of Mainframe computers running under IBM's MVS operating systems have a need to merge migrate data from multiple smaller DASD devices (disk volumes) to larger DASD devices, and/or to migrate data in order to combine data set extents. A method is disclosed for migrating data where a volume merge is involved, and/or when combining of extents is desired, that minimizes the down time of applications using the involved data while satisfying MVS rules for volume and catalog meta-data files as well as data extent limitations. The method may be implemented such that source and target volumes need not be in like manufacturer DASD devices.

Abstract: MVS mainframe computer systems employ the ICF (Integrated Catalog Facility) catalog environment to manage numerous data sets. To provide nearly continuous availability of those data sets, the BCS catalog (250,270) must be re-organized while leaving the catalog open to access by applications. To perform a re-org while open, a data CI correlation table (500) can be constructed (314) and used to lay the data CIs into a backup file in logical order (316), so that they can be loaded into the new BCS catalog (324) without sorting, thereby reducing downtime.

Abstract: MVS mainframe computer systems employ the ICF (Integrated Catalog Facility) catalog environment to manage numerous data sets. To provide 24×7 availability of those data sets, the BCS (250,270) must be re-organized while leaving the catalog open to access by applications. To perform a re-org while open, a data CI correlation table (500) is constructed (314) and used to lay the data CIs into a backup file in logical order (316), so that they can be loaded into the new BCS (324) without sorting, thereby reducing downtime. Additionally, if the BCS is damaged during normal operation, repair of the structure must also be performed to ensure that correct access is maintained to all data that is cataloged in the BCS. Throughout the re-org process, structural integrity checks are performed on the data and index component of the BCS, and if errors are encountered, they can be repaired.

Abstract: Users of Mainframe computers running under IBM's MVS operating systems have a need to merge migrate data from multiple smaller DASD devices (disk volumes) to larger DASD devices, and/or to migrate data in order to combine data set extents. A method is disclosed for migrating data where a volume merge is involved, and/or when combining of extents is desired, that minimizes the down time of applications using the involved data while satisfying MVS rules for volume and catalog meta-data files as well as data extent limitations. The method may be implemented such that source and target volumes need not be in like manufacturer DASD devices.