Separating Nonstop Sql Tables; Compressing Audit Data For Tables And Files; Preparing The Backup System - HP NonStop RDF J-series RVUs Management Manual

Separating NonStop SQL Tables

It is recommended that you avoid registering NonStop SQL tables protected by RDF in the same
catalogs as tables that are not protected by RDF. Separating protected tables from unprotected
ones simplifies the comparison of primary system catalogs with backup system catalogs.

Compressing Audit Data for Tables and Files

Although not required by RDF, using the AUDITCOMPRESS file attribute will enhance RDF
performance. TMF compresses the audit data generated for NonStop SQL tables and Enscribe
files for which AUDITCOMPRESS is ON. For applications involving updates of only a few bytes
to large existing rows or records, this audit compression greatly reduces both the amount of
audit records the extractor must read and send to the receiver and the corresponding amount of
RDF traffic on the communications line.
For NonStop SQL tables and indexes, AUDITCOMPRESS is the default. If the value has been
changed to NO AUDITCOMPRESS for a table, you can use an ALTER TABLE command, entered
through the NonStop SQL conversational interface, to reset the default value:
ALTER TABLE table-name AUDITCOMPRESS;
For Enscribe files, the default for AUDITCOMPRESS is OFF. To turn off the AUDITCOMPRESS
attribute for an Enscribe file, use the File Utility Program (FUP) to enter an ALTER command:
FUP ALTER filename, AUDITCOMPRESS

Preparing the Backup System

Before starting RDF, you need to copy every database, program, and file that the primary system
applications use to the backup system so that the backup system can take over in the event of a
primary system failure. In the backup copies, you need to change any occurrences of the primary
system name to the backup system name. RDF replicates the database; you should use the
NonStop Autosync product to replicate everything else that is not audited, such as important
application files, objects, and scripts.
If the names of any volumes or devices that the applications might use on the backup system
are different from the names on the primary system, you must also change any references to
these volumes or devices.
It is strongly recommended that the backup system have one volume for every volume protected
by RDF on the primary system and that each backup volume have the same name as the
corresponding primary volume. If the backup volume names are not identical to the primary
volume names, then you need to update every backup partitioned file and every backup file that
has alternate keys so that each points to the right volume name. Also, if you replicate two or
more volumes on the primary system to a single volume on the backup system, the updaters
might fall behind under very high throughput due to the double workload on the underlying
disk process.
RDF requires that TMF be started on the backup system, the database on the backup system
resides on configured data volumes, the data volumes be physically up, and the files and tables
be audited. BEGINTRANS should be enabled. SMF disks should be audited. If replicating NonStop
SQL Format 2 audit data, be sure the backup system supports it.
For NonStop SQL databases, you must create catalogs on the backup system and you need copies
of the following objects on the backup system:
• Catalogs in which base tables protected by RDF and objects dependent on those base tables
are registered, preferably with the same names as the primary system catalogs
• All base tables that reside on primary system volumes protected by RDF
• All views and indexes dependent on base tables protected by RDF
• All program files for applications that use any base tables protected by RDF if you want the
applications to run at the backup site after an RDF takeover operation
70 Installing and Configuring RDF