CA FAVER (Fast VSAM Export Restore) VSAM Data Protection is a utility program that backs up and restores VSAM clusters. Following are the features of CA FAVER:
CA FAVER output is compatible across all z/OS operating systems; the files created on one system can be restored on any other z/OS system. Full support exists for any IBM supported and maintained VSAM data format that resides on any DASD device supported by IBM. Because CA FAVER is expressly designed to use the logical relationships of VSAM catalogs, data spaces, and clusters, it introduces a new concept in the efficient protection of VSAM databases.
High performance is achieved, in part, by exporting only actual data minus all inherent free space. This contrasts with currently available physical dump/restore programs that can only dump and restore DASD track groups which, hopefully, contain the data, but also typically contain much useless free and/or unallocated space. High performance is further achieved by employing a specially designed export access method.
Data integrity is assured by a combination of factors, the most important being simply that data integrity was a prime consideration influencing all design criteria for CA FAVER.
First, CA FAVER accesses VSAM clusters logically; in the process, it verifies the structural integrity of the cluster's components. That is, CA FAVER does not just dump physical track images which may or may not represent a viable data space. Rather, it examines the actual data relationships within a cluster, then only exports logical records when their correctness has been assured.
Because CA FAVER exports logical clusters and not just physical track groups, it inherently preserves the intricate synchronization between master catalogs, user catalogs, and data spaces. All considerations applying to the VSAM-mandated coordination between backup and restore of catalogs and data spaces when using any type of purely physical backup technique simply do not apply to CA FAVER. Also, CA FAVER identifies the data on the backup file by cluster name, not relying on a cluster's physical position on the file.
The ability of CA FAVER to automatically dump every cluster defined in a catalog also serves to promote data integrity in a VSAM database. Because each cluster need not be named, it means there is no chance of accidentally missing or dropping an important cluster during a backup. CA FAVER can be easily instructed to back up all clusters defined in a catalog or an SMS storage group, which ensures nothing is missed.
Because CA FAVER can automatically redefine a cluster during its restore, it is not necessary to define clusters as reusable just to provide for a convenient restore. Not requiring clusters to be defined as reusable promotes data integrity, since the entire contents of a reusable cluster are lost if the cluster is accidentally opened for output.
The CA FAVER utility also provides a feature which allows the data integrity of all or any portion of an export file to be checked. Immediately after creating an export file using CA FAVER, any logical cluster, aggregate group of clusters, or the entire file can be compared byte for byte with the original disk file. A completely different VSAM access method is used for this process, assuring that the dump is readable and independently verifying the exactness and sequence of the data.
Ease of use is promoted within CA FAVER through a comprehensive aggregate cluster reference facility. Of course, an individual cluster can always be specifically accessed, but CA FAVER also allows groups or families of clusters to be referenced as well. For example, CA FAVER can be instructed to operate on all clusters defined in a particular catalog; you do not have to name or supply JCL for each cluster. Another variation of the CA FAVER aggregate reference facility is the ability to export all clusters residing on specific DASD volumes, SMS storage groups, or all clusters having common name characteristics. At an aggregate cluster level, indicated clusters can be excluded from the group to be considered for export or restore.
To further CA FAVER ease of use, very few control statements are required. For example, during the export process CA FAVER not only copies the data but also stores all of the catalog's information necessary to delete and redefine the cluster during any subsequent restore. This allows CA FAVER to restore any cluster without requiring all the detailed data normally necessary for IDCAMS to delete and define a cluster.
To suit each user's needs, CA FAVER provides maximum flexibility in data manipulation through a user exit facility. After examining a record during restore processing, the exit can direct CA FAVER to restore the record as is, delete it, replace it with a modified version, or insert new records.
This guide is intended as an aid to the effective and efficient use of CA's CA FAVER utility program for backing up and restoring VSAM clusters. It describes in detail how to use CA FAVER and documents the associated features, functions, samples, codes, and reports.
This section contains the following topics:
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