HP NonStop RDF, Руководство по управлению

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2 Preparing the RDF Environment
Before RDF can be run on a NonStop system, the system configurations and user applications
must meet certain RDF requirements. This chapter explains how to prepare each system for RDF
installation and operation, ensuring that all these requirements are met and that you understand
the RDF product’s restrictions. This information, intended for all readers, covers the following
tasks:
• “Configuring Hardware for RDF Operations” (page 57) , including primary and backup
system configurations, disk volume considerations, and network requirements
• “Preparing Software and Database Files for RDF Operations” (page 59) , including TMF and
RDF considerations, NonStop SQL database conventions, Enscribe database conventions,
and application design factors
• “Using SMF With RDF” (page 65)
Configuring Hardware for RDF Operations
The RDF hardware requirements are summarized in Table 2-1 and described in detail in the next
few pages.
Table 2-1 RDF Hardware Requirements
Requirements Hardware
RDF runs on NonStop systems under control of the
NonStop operating system. Each RDF primary system
must be connected through an Expand path to its RDF
backup system. Primary and Backup Systems
The RDF product transmits data on any Expand data
communications lines. Communications
Primary System Configuration
The RDF primary system must operate under control of the NonStop operating system, which
is the standard operating system for NonStop systems. This system must be connected over an
Expand data communication path to one or more RDF backup systems.
Backup System Configuration
The RDF backup system, like the primary system, must operate under control of the NonStop
operating system and be connected over an Expand path to one or more RDF primary systems.
In the event of a disaster at the primary site, an identical copy of the primary system’s hardware
configuration ensures that the backup system can support your business operations without
lowering system performance. If the backup system’s configuration is identical to that of the
primary system, your system personnel can adjust more quickly to the backup environment
during disaster recovery.
If you choose not to configure the backup system as an identical copy of the primary system,
plan the configuration of the backup system with enough processing power and disk drives to
enable RDF to keep the backup database current with the primary database.
Because RDF applies database modifications on the backup system through a private low-level
and privileged interface to the disk process, by-passing the file system, the CPU requirements
on the backup system when running RDF will typically be lower than the total CPU requirements
on the primary system running the applications. Repeated analysis has shown that the cost of
replication on the backup system is usually 25% or less than the cost on the primary system. The
actual backup CPU requirements depend on many factors, including the RDF configuration, the
Configuring Hardware for RDF Operations 57