Recovering HALDB databases when enabling partitions

When a partition is enabled, it is flagged in the RECON data set as needing recovery. When recovering an enabled partition, you must also recover any partitions that were affected when the partition was disabled.

If updates were made to the HALDB database after the partition was disabled, you will likely have to recover the entire HALDB database, as well as any other HALDB databases that are logically related to the HALDB database that contains the partition being enabled.

To enable a partition as part of recovery:

Procedure

  1. Enable the partition by using one of the following methods:
    • The HALDB Partition Definition utility
    • The DBRC command CHANGE.PART DBD(HALDB_master_name) PART(partition_name) ENABLE
    DBRC marks all of the database data sets in the enabled partition as needing recovery.
  2. By using the image copies taken before the partition was disabled, recover all of the partitions that changed when the partition was disabled or that were changed by applications after the partition was disabled.

    If updates were made to the databases after the partition was disabled, you must perform a time stamp recovery.

  3. Make the partitions available again by issuing either the /START DB partition_name command or the UPDATE DB NAME (partition_name) START(ACCESS) command.
  4. If the online IMS system does not immediately recognize the enabled partition, issue either a /START DB HALDB_Master OPEN or UPDATE DB NAME(HALDB_Master) OPTION(OPEN) command to rebuild all of the online partition structures of the HALDB database.