HP NonStop RDF, Руководство по управлению

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When you issue a STOP RDF command on the backup system, RDFCOM attempts to contact
the RDF monitor on the primary system. After discovering that the monitor is not accessible,
RDFCOM sends individual stop messages to all RDF processes on the backup system.
If RDFCOM can contact the monitor on the primary system, the STOP RDF command is aborted.
To stop the RDF processes on the backup system, RDFCOM must be able to locate the RDF
control subvolume (whose name is the same as that of the control subvolume on the primary
system). You must explicitly specify the control subvolume name when you start the RDFCOM
session. For example, if the associated primary system is named \DALLAS and you did not
specify a suffix in the INITIALIZE RDF command, start the RDFCOM session on the backup
system:
>RDFCOM DALLAS; STOP RDF
If the associated primary system is named \DALLAS and you specified the suffix “3” in the
INITIALIZE RDF command, start the RDFCOM session on the backup system:
>RDFCOM DALLAS3; STOP RDF
An alternative way to stop RDF on the backup system is to enter the following command through
TACL:
>STATUS *, PROG RDF-software-loc.*, STOP
CAUTION: Issuing this command in this situation is only safe, however, if this is the backup
system for a single RDF environment.
Stopping RDF Using STOP RDF, DRAIN
As stated above, stopping TMF shuts down RDF and it guarantees that the backup database is
then logically identical to the primary database. If, however, you have several different
applications running on your primary system, each working on its own database, and if not all
are protected by the one RDF subsystem, then you may not want to stop TMF just to shutdown
the RDF subsystem. In this situation, you can use the STOP RDF, DRAIN command, but you
must observe the following sequence of steps.
1. Stop the application that is updating your RDF-protected database.
2. Enter the STOP RDF, DRAIN command.
In response to the DRAIN command, the extractor marks its location in the audit trail when it
receives notice of the operation, and the updaters do not shut down until they have processed
all audit up to that location. Finally, the purger process generates RDF event 852 to notify you
that the operation has completed. Since your application has previously stopped, your backup
database is now logically identical to your primary database that is protected by this RDF
subsystem, and you have not had to stop TMF to get into this state. When you are ready to restart
RDF, just enter the START RDF command and it will resume where it left off last.
CAUTION: If you do not stop the application that is updating your RDF protected database
until after you have issued the STOP RDF, DRAIN command, then the backup database has low
probability of being logically identical to the primary database after RDF shuts down. If this
happens and the application is still down, then just restart RDF and then enter a new STOP RDF,
DRAIN command after the Extractor shows an RTD time of 0:00.
Stopping RDF using STOP RDF, REVERSE Operation
This operation is only useful for the special situation involving a switchover operation. See the
section on STOP RDF, REVERSE and the Reverse Trigger further below for a description of when
you would use this operation.
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