SQL/MP Installation and Management Guide

HP NonStop SQL/MP Installation and Management Guide—523353-004
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Planning Database Security and
Recovery
Database security and recovery are two important topics to consider before creating a
database:
•
Planning for security and implementing an authorization scheme is the primary
protection against unauthorized user intervention. Security, however, cannot
eliminate errors by authorized users.
•
Planning for recovery is essential for protecting your database. Your recovery plan
should include protection against disk failures, software failures, application errors,
other equipment failures, catastrophic disasters, and human errors of all types.
HP NonStop software provides several online recovery mechanisms, including:
•
Mirrored disk volumes are a primary protection against disk failures. These
volumes also provide the ability to repair and maintain disk volumes online, without
interrupting application processing.
•
The TMF subsystem provides the best online protection against application or
equipment failures. When used correctly, the TMF subsystem protects the
database from program failures that would leave the database inconsistent
because of incomplete transactions.
•
The use of backup tapes of the data files can provide a way of protecting data in an
offline mode. Tapes can be physically removed from the site and saved for
possible disaster recovery.
•
The Remote Duplicate Database Facility (RDF) maintains replicated databases at
a remote site that can be used for contingency planning. As end users modify the
local database, RDF replicates those changes in the remote database, keeping it
continuously up to date. For more information about managing a replicated
SQL/MP database with RDF, see the RDF/IMP and IMPX System Management
Manual.
NonStop fault-tolerant hardware and software strategies provide maximum protection
against most equipment failures, power failures, and some catastrophic failures. This
protection, however, does not eliminate the need to plan carefully to protect your
database and application software. After formulating a comprehensive recovery
strategy, practice carrying out the plan on a regular, consistent basis.