Chapter 6. Using Catalog RecoveryPlus 85
6.4.6 Alias processing with BACKUP BCS
If the default keyword, ALIAS, is in effect for the BACKUP command, all related
aliases for the BCS are copied from the current master catalog to the backup
copy at the start of backup for each BCS. If a subsequent RECOVER process is
executed, these aliases are restored to the master catalog on the system running
the RECOVER command. It is also possible to recover ALIASONLY, allowing you
to use this facility to replicate aliases to multiple master catalogs. If, for some
reason, you do not want aliases backed up at all, you can specify NOALIAS on
the BACKUP command.
6.4.7 BACKUP BCS bypasses index processing
The Catalog RecoveryPlus BACKUP command automatically opens the BCS as
a data set. In other words, the Access Method Control Block (ACB) indicates that
we are opening an ICF catalog, but the open process takes place outside of
catalog management. The command specifically opens the data component of
the BCS for read access, without using the index. With this logic, BACKUP does
not need to worry about index errors. It reads through the data component of the
BCS in
physical sequential order, deblocking records from the CIs within the
BCS, reblocking them, and writing them out to the backup.
This is unlike most other BCS backup tools, such as EXPORT, which open the
BCS as a catalog in other words, as a KSDS. If there are corruptions to the
index, the result can be unrecoverable backup failures.
Section 7.1, Case study #1: Ensuring good backups on page 113, illustrates the
importance of this logic, where the specific type of BCS corruption resulted in
IDCAMS EXPORT not being able to back up all of the records in the BCS,
whereas the Catalog RecoveryPlus BACKUP backed up the entire BCS. The
difference was specifically due to this processing logic.
6.5 RECOVER command
The Catalog RecoveryPlus RECOVER command provides the ability to restore
or forward recover either part of an ICF catalog, a BCS or a VVDS, from a backup
copy that was created either by IDCAMS EXPORT (BCS only) or the CR+
BACKUP command.
If the backup was created by CR+ BACKUP, the records are first sorted and then
written to the BCS or VVDS being recovered. This logic alerts you (by way of
informational or error messages) to any duplicate key records that are identified.

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