RDF/IMP and IMPX System Management Manual (RDF 1.3+)

Introducing RDF
Compaq NonStop™ RDF/IMP and IMPX System Management Manual—522204-001
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Features
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Flexibility in protection
You can run RDF with updating on the backup system either enabled or disabled.
RDF is also very flexible with regard to system interrelationships and to disk usage
requirements on backup systems. Besides the most basic configuration of a single
primary system protected by a single backup system, you can have any of the
following:
•
Multiple primary systems protected by one backup system.
•
Reciprocal protection between two systems, where each is the backup to the
other (different databases on the two systems).
•
A single primary system whose database changes are replicated to databases on
multiple backup systems. Such an environment makes possible simultaneous
read-only access to all of the backup databases (this is desirable for query-
intensive applications such as telephone directory assistance).
•
Triple contingency—a special instance of the database replication feature
whereby a single primary system is protected by two identical backup systems.
This feature allows your applications to resume, with full RDF protection,
within minutes after the loss of your primary system, provided the two backup
systems are not too far behind.
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
exits on any backup volume. (For information on partitioned files, see the Guardian
User’s Guide.)
•
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 SQL/MP or Enscribe). Unstructured Enscribe files are not supported.
Enscribe format-2 files (Big Files) and SQL format-2 tables and partitions are
supported.
•
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.
•
Subvolume and file replication
In addition to volume replication, the RDF/IMP and IMPX products support
replication of selected subvolumes and files.