RDF/IMP and IMPX System Management Manual (RDF 1.4+)

Online Database Synchronization

HP NonStop RDF/IMP and IMPX System Management Manual—524388-001

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Synchronizing Selected Database Portions Online

There are a number of reasons why you might want to synchronize only selected

portions of your database. For example:

•

If you have a large database, it might be easier to break the total number of

volumes into subsets, and then synchronize one subset at a time.

•

If a file or table has become corrupt, you might want to synchronize just that one

file.

•

If an individual partition of a file or table has become corrupt, you might want to

synchronize just that one partition.

Overview

To synchronize selected portions of your database, you follow the same steps as those

for synchronizing an entire database.

Example #1 – Staged Synchronization of an Entire Database

Suppose you are synchronizing your entire database by synchronizing selected

portions first. Suppose your database is on ten volumes and you want to synchronize

two volumes at a time. You would start by synchronizing your first two volumes,

following the guidelines for synchronizing an entire database.

When this operation has completed and the RDF updaters are fully caught up, you

stop the NonStop RDF product. You then delete your current RDF configuration and

initialize a new RDF subsystem, using the SYNCHDBTIME option. For the timestamp

to be used with the SYNCHDBTIME parameter, you specify a timestamp following the

guidelines for the INITTIME option.

When you create your new RDF configuration, include the first two volumes you have

just synchronized and include two new volumes. Regarding the first two volumes that

are already synchronized, you do not need to create and load copies of the files and

tables on those volumes because they are already synchronized. For the two new

volumes, you need to synchronize these following the steps for an entire database

synchronization.

When these two new volumes have been synchronized, you follow the same

procedure discussed above, and adding two new volumes to your new RDF

configuration file.