HP NonStop RDF, Руководство по управлению

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Figure 1-1 Basic RDF Configuration
In Figure 1-1 , there are 20 audited volumes on the primary system ($D1 through $D20). Only
volumes $D1 through $D15, however, are configured for RDF protection.
Audit records for volumes $D1 through $D10 and $D16 through $D20 are sent to the master
audit trail (MAT). The RDF master extractor process reads the MAT and sends audit records
associated with volumes $D1 through $D10 to the RDF master receiver process on the backup
system.
Audit records for volumes $D11 through $D15 are sent to the auxiliary audit trail. The RDF
auxiliary extractor process reads the auxiliary audit trail and sends audit records associated with
volumes $D11 through $D15 to the RDF auxiliary receiver process on the backup system.
The master receiver writes transaction status information to the master image trail. In this example,
each receiver process writes all audit records to a single secondary image trail. As will be discussed
later, however, either could write to multiple sorted image trails.
Updater processes $UP1 through $UP10 read audit records from the secondary image trail and
apply it to volumes $D1 through $D10, respectively, on the backup system. For example, updater
process $UP1 only looks for audit records for tables and files associated with volume $D1 on the
primary system (ignoring any for volumes $D2 through $D10), and applies that information to
the corresponding tables and files on $D1 on the backup system.
Updater processes $UP11 through $UP15 read audit records from the AUX01 secondary image
trail and apply it to volumes $D11 through $D15, respectively, on the backup system.
As mentioned earlier, the RDFCOM process on the primary system provides the user interface
for issuing RDF commands. The RDF monitor process coordinates user commands among the
RDF processes and monitors those processes during all RDF states.
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