RDF/IMP, IMPX, and ZLT System Management Manual

Introducing RDF
HP NonStop RDF/IMP, IMPX, and ZLT System Management Manual—524388-002
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Audit-Fixup Process
In response to the UNPINAUDIT command, RDFCOM issues a prompt asking you to
confirm your request.
If the files are unpinned successfully, RDFCOM issues an informational message to
that effect.
If an error occurs while attempting to unpin the audit trail files, the command is ignored,
and RDFCOM issues a message indicating the error.
Audit-Fixup Process
The audit-fixup process only ever runs on the remote standby system in an RDF ZLT
environment. The audit-fixup process performs file-fixup operations on audit-trail files
on the ZLT remote mirror that have been left with the CRASHOPEN flag set following a
failure of the RDF primary node. The audit-fixup process is started by an extractor
whenever the extractor attempts to read an audit-trail file that has the CRASHOPEN
flag set. Unlike the other RDF processes, the audit-fixup process does not persist for
the duration of the RDF environment. The audit-fixup process is started on demand by
the extractor process, and terminates as soon as it has performed the file-fixup
processing on the audit-trail file.
This process does not run as process pair, but the extractor will start a new audit-fixup
process if the audit-fixup process is terminated due to a processor failure. No
configuration parameters are required for the audit-fixup process. The audit-fixup
process runs in the same CPU as the extractor primary process with a process priority
one less than the extractor priority.
Receiver Process
A receiver process is a process pair that runs on the backup system. There is one
receiver for each configured extractor. A receiver process accepts audit records from
its extractor, sorts them, and then writes them to the appropriate RDF image trail, as
shown in Figure 1-6. (The restartability of a receiver ensures the receiver's correctness
at process takeover or under any conditions requiring resynchronization with its
extractor.)
A receiver determines which updater will apply the data, and sorts the data into the
image trail used by that updater. The records in the image trails are subsequently used
by updater processes to update the backup database.
Each receiver also creates image trail files, preallocates extents, and initiates rollovers.