HP NonStop RDF, Руководство по управлению

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13 Auxiliary Audit Trails
In addition to the Master Audit Trail (MAT), RDF/IMPX and ZLT support protection of up to 15
auxiliary audit trails.
If you want to protect data volumes associated with an auxiliary audit trail, you must configure
an auxiliary extractor and an auxiliary receiver for that trail. Thus, for each auxiliary audit trail,
there will be one auxiliary extractor-receiver pair.
Auxiliary Extractor
An auxiliary extractor can only be configured to a single auxiliary audit trail. Such an extractor
will read only the designated auxiliary audit trail; it will never read any part of the MAT or any
other auxiliary audit trail. When reading the audit trail, it looks for any audit records associated
with the pool of volumes being protected by RDF (normal filtering logic). All such records are
sent to the backup system in accordance with standard RDF architectural behavior. Each auxiliary
extractor is associated with a corresponding auxiliary receiver through the user-specified
configuration. The auxiliary extractor communicates only with that particular auxiliary receiver,
and never sends data to the master receiver or any other auxiliary receiver.
Auxiliary Receiver
An auxiliary receiver is associated with a specific auxiliary extractor. Because the auxiliary
extractor sends audit records associated only with its particular auxiliary audit trail, the
corresponding auxiliary receiver writes audit records to the image trails of updaters associated
only with volumes configured to the particular auxiliary audit trail.
For example, assume that $DATA1 on the primary system is configured as a data volume in
auxiliary audit trail AUX01, and an auxiliary extractor is configured for AUX01. The auxiliary
extractor sends all audit records for $DATA1 to a corresponding auxiliary receiver on the backup
system. The receiver writes the data to an image trail that is, in turn, read and processed by an
updater responsible for replicating database changes for $DATA1.
Configuring Extractors and Receivers
The SET EXTRACTOR and SET RECEIVER commands include this optional syntax:
ATINDEX atindex
where
atindex
is an integer value corresponding to the audit trail number of the MAT (0) or
an auxiliary audit trail (1 through 15) on the primary system. The default is 0.
Because 0 is reserved for the MAT, the extractor and receiver with an
atindex
value of 0 are
the master extractor and receiver. The extractors and receivers with
atindex
values of 1 through
15 must protect volumes associated with configured auxiliary audit trails AUX01 through AUX15,
respectively.
A master extractor and receiver are required, because TMF control records are required on the
backup system in the event of an RDF takeover operation or a stop-update-to-time operation.
Auxiliary extractors and receivers are optional.
For each extractor, there must be a corresponding receiver with the same
atindex
value.
Error conditions
• It is an error not to have a master extractor (
atindex
value of 0).
• It is an error not to have a master receiver (
atindex
value of 0).
• It is an error if you do not have an auxiliary extractor and receiver with the same
atindex
value. That is, if you have an auxiliary extractor with an
atindex
value of 1, you must have
an auxiliary receiver with an
atindex
value of 1.
Auxiliary Extractor 291