RDF System Management Manual for H-Series RVUs (RDF 1.8)

UNPINAUDIT
CAUTION: Before deleting an RDF configuration, always issue an UNPINAUDIT command
to unpin any audit-trail files that might be pinned by the configuration. If you delete the
configuration without first doing so, then you will be unable to unpin the files afterward.
If you unpin files, RDF cannot be restarted if the files required by the extractor cannot be made
available. When you unpin audit-trail files, be sure that these files are dumped to disk or tape.
If they are not dumped, and the TMP renames the file or files required by the extractor, you will
have to reinitialize RDF and resynchronize the primary and backup databases.
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.
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.
Sorted Image Trails
RDF maintains its image data on disk volumes specified during RDF configuration. On each of
these volumes, the collection of files that contains image data is known as an image trail; that
is, there is one image trail per individual image trail volume.
The standard image trail used by RDF, called the master image trail, contains the transaction
status records that hold key information about whether a transaction has committed or aborted.
The master image trail is stored on the disk volume selected by the master receiver’s RDFVOLUME
configuration option. You cannot configure any updaters to the master image trail.
All updaters must be configured to secondary image trails. You can configure up to 255 secondary
image trails in addition to the master image trail. Each secondary image trail is stored on a
separate volume, selected through the IMAGETRAIL configuration option.
RDF uses multiple sorted image trails. With this feature, the receiver detects which updaters are
associated with which image trails. When it receives a record, the receiver identifies the updater
that will apply the record to the backup database. The receiver then sorts the record into the
appropriate image trail, and the record is written to that image trail.
50 Introducing RDF