Recovery

The recovery function recovers a backup version to a level 0 volume. Recovery must be initiated by a command.

The data set recovery function refers to the process of recovering a data set to its condition as of a specified date.

You can recover individual data sets by entering an HRECOVER line operator on an ISMF panel or by issuing the HRECOVER command.

DFSMShsm can recover data sets from a DFSMShsm backup version or from a DFSMShsm dump copy. For a data set to be restored from a dump copy, the dump copy must have been made from a dump class that allows data set restore, and a VTOC copy must exist for the dump (except when an authorized user explicitly specifies a dump volume). Dump copies created by the fast replication process are not used for recoveries by the RECOVER nor HRECOVER commands.

DFSMShsm automatically chooses the most recent copy of the data set unless directed otherwise by options you specify with the HRECOVER command, or by options set by your installation’s system programmer.

If the data set is SMS-managed at the time of recovery, the target volume is determined by the data sets storage class and storage group. If the data set is not SMS-managed, then the target volume is selected in the following order:

The target volume specified
The volume on which the target data set is currently cataloged
The volume from which the data set was originally backed up or dumped

The volume recovery function refers to the process of recovering a level 0 volume to its condition as of a specified date.

DFSMShsm volume recovery can use incremental backups or full-volume dumps, or both. A DFSMShsm-authorized user can issue one RECOVER command that is used to request both a volume restore and an incremental volume recovery.

See Figure 1 and Figure 2 for an overview of the flow for the automatic incremental backup and the recovery/restore functions.

Figure 1. Flow of Automatic Incremental Backup

Figure 2. Flow of Recovery/Restore Functions