RDF/IMP and IMPX System Management Manual (RDF 1.3+)

Introducing RDF

Compaq NonStop™ RDF/IMP and IMPX System Management Manual—522204-001

1-26

Online Database Synchronization

With RDF/IMPX you can synchronize entire databases or selected volumes while your

applications continue to run. For information about this capability, see Section 7, Online

Database Synchronization.

Online Dumps

With RDF/IMP and IMPX all backup databases are audited by TMF. Among other

things, this means that you can take online dumps of a backup database at any time,

thereby minimizing the amount of time necessary to perform any subsequent takeover

operation. For information about taking dumps while the updaters are running, see

Section 5, Managing RDF.

EMS Support

RDF/IMP and IMPX both support the Event Management System (EMS). They direct

their command, event, warning, and error messages to an EMS collector in the form of

fully-tokenized messages.

You can view messages in the EMS log online using Viewpoint or any other tool you

normally use for monitoring $0. Note that when you do so you are perusing the entire

EMS log. You can, however, use the standard EMS filter RDFFLTO to isolate RDF

messages into an entry-sequenced file which you then can examine using the RDFSCAN

online utility.

SMF Support

There are two ways to use NonStop™ Storage Management Foundation (SMF) logical

volumes:

•

Map many physical volumes to a single logical volume

In this configuration, you create a single logical volume comprised of a pool of

physical volumes. Thus, the name of your file or table includes the name of the

logical volume (not the physical volume) on which it resides.

•

Map many logical volumes to a single physical volume

In this configuration, you can have a very large physical disk volume subdivided

into a number of smaller logical volumes. In this way it is possible to have multiple

partitions of a file residing on a single physical volume, with each partition of the

file stored on a different logical volume.

All of the RDF products support both of the above usages on the primary system. On the

backup system, however, they support only the second usage. Consequently, if you

configure an updater to a logical volume comprised of a pool of physical volumes, your

RDF configuration will fail validation and you will not be able to execute a START RDF

command successfully.