Mainstar ICF Catalog Recovery Plus Update

Published 18 December 2006

Authors: Mary Lovelace


Mainstar Catalog RecoveryPlus is a tool you can use to recover your ICF catalogs. ICFRU is a basic tool to help you in a forward recovery situation.This technote provides an introduction to the Mainstar CatalogRecovery Plus tool.


ICF catalogs are essential system data sets. Even with today’s high availability storage subsystems and processors, there are still situations in which you need to recover your catalogs. You should keep your catalogs healthy and be prepared for a recovery situation. Also, you need to be sure that your recovery procedures do not have a big impact on your production environment. To minimize the recovery process, you should have a clear backup and recovery strategy, and the proper utilities.

IBM® Integrated Catalog Forward Recovery Utility (ICFRU) and Mainstar Catalog RecoveryPlus are two of the tools you can use to recover your catalogs. ICFRU is a basic tool to help you in a forward recovery situation. It does not offer a wide range of features, but is useful for catalog recovery. Mainstar Catalog RecoveryPlus offers a set of features to help you in your ICF catalog environment maintenance.

With Catalog RecoveryPlus, you can back up and recover ICF catalogs, both the BCS and VVDS, including forward recovery with SMF records. You can also perform catalog diagnostic and troubleshooting functions, as well as day-to-day catalog maintenance.

As a reminder, catalogs do break. If you are not prepared for it, your system could have a serious outage in accessing thousands, tens of thousands, or hundreds of thousands of data sets. ICF catalogs, including both BCSs and their related VVDSs, are software structures. This means that they are accessed and updated by software – catalog management, to be exact – and this is very complicated software.

Catalogs are often shared across multiple systems, where in-storage control blocks and buffers are maintained and accessed by each individual system during open, close, and update processing of your data sets. This creates a very complex environment in which catalog management operates. All it takes is the smallest failure in the software code, and you risk a catalog failure. Catalog backups, taken frequently and accurately, are your first level of insurance against a failure. Your second level of insurance is knowing how to recover a catalog from a failure, and completing that recovery in the shortest possible time.

To accomplish this, you need to ensure that all catalogs in your environment are being backed up, as frequently as you can possibly afford to. At a minimum, make sure that you back up your catalogs at least once a day. For heavily updated catalogs, consider backups that are taken multiple times a day.

Do not think that the BCS is the only part of your ICF catalog environment that needs to be backed up. If you have a complex DB2® environment, for example, spanning across dozens of disk volumes, you should consider backing up the VVDSs on those volumes. This provides a safeguard against a VVDS failure on one volume that would otherwise require you to recover the databases across all of those volumes, and then bring them up to date from those backups. VVDS backups with Catalog RecoveryPlus are very fast, proving to be a small cost compared to the time it would take to recover from the failure of a VVDS.

Finally, the only way to know how to recover an ICF catalog, whether it is a BCS or VVDS, is through practice. Your installation almost certainly practices its disaster recovery plan, and you should practice catalog recovery as well. It is advised that you not practice this recovery while at your DR site, but rather, practice recovery at your primary site, and on your production catalogs and volumes. This can most easily be done through simulation capabilities, and that is possible with Catalog RecoveryPlus.

The following Catalog RecoveryPlus commands are covered in detail in the IBM Redpaper titled ICF Catalog Backup and Recovery: Catalog RecoveryPlus Update, REDP-4214.

  • ZAP (PRINT, DELETE, PATCH functions)
  • MAP

The Redpaper provides information and practical examples about how to use Catalog RecoveryPlus in a catalog recovery situation. It also provides useful recommendations for storage administrators in implementing a catalog backup and recovery plan. It also provides a variety of practical tests to help you with the different error scenarios you might find in your daily production activities.

Special Notices

This material has not been submitted to any formal IBM test and is published AS IS. It has not been the subject of rigorous review. IBM assumes no responsibility for its accuracy or completeness. The use of this information or the implementation of any of these techniques is a client responsibility and depends upon the client's ability to evaluate and integrate them into the client's operational environment.

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