RDF/IMP, IMPX, and ZLT System Management Manual

Introducing RDF
HP NonStop RDF/IMP, IMPX, and ZLT System Management Manual—524388-002
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Features
RDF does not require an identical one-to-one volume relationship between
volumes on the primary system and those on the backup system. Backup volume
names do not have to match primary volume names. The subsystem can direct
audit information from more than one audited volume on the primary system to a
single volume on the backup system, provided that no more than one partition of a
file exists on any backup volume. (For information on partitioned files, see the
Guardian User’s Guide.)
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Application independence
RDF is application-independent; it can protect data for any application that uses
NonStop SQL/MP entities (tables, indexes, or views) or Enscribe record manager
files audited by TMF.
RDF supports the following audited file types: key-sequenced, entry-sequenced,
and relative (for NonStop SQL/MP or Enscribe) and Enscribe queue files.
Unstructured Enscribe files are not supported.
Enscribe format-2 files (Big Files) and NonStop SQL/MP format-2 tables and
partitions are supported.
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Master and auxiliary audit trail protection
RDF can protect all tables and files that are being audited by TMF, whether they
are associated with the master audit trail (MAT) or an auxiliary audit trail.
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Subvolume and file replication
In addition to volume replication, the RDF/IMP and IMPX products support
replication of selected subvolumes and files.
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Economical processing
RDF conserves resources at both sites. The extractor typically uses 1% of the
resources used by the application on the primary and 4% of the Expand resources.
On the backup system the cost of an updater process replicating an update
operation is typically 15-25% of the original cost to do the operation on the primary
system.
On the primary system RDF uses just one process (the extractor) per audit trail to
read and transmit audit information to the backup system. The extractor process
automatically filters out any audit information not relevant to the backup database.
On the backup system RDF stores and applies all audit information without using
any primary system resources.
RDF helps balance the load between the primary and backup systems. For
example, to reduce the application load on the primary system, you can perform
database queries on the backup system; RDF does not, however, guarantee
database consistency while changes are being processed for a transaction.