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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Support for Network Transactions

The RDF/IMPX and ZLT products support network transactions: transactions that

update data residing on more than one RDF primary system.

More specifically, the updates for a transaction on one of the two primary systems may

have been successfully transmitted and applied to the associated backup database,

but a disaster brought down the other primary system before the updates by the

transaction on that system could be sent to its backup database. After executing RDF

takeover operations on both backup systems, the data from the network transaction

would be present in one backup database but not in the one brought down by the

disaster. Thus the distributed backup database is inconsistent with regard to the

affected network transaction.

For information about this capability, see Section 13, Network Transactions.

RDF and NonStop SQL/MX

RDF can replicate NonStop SQL/MX user tables and indexes as well as NonStop

SQL/MP objects and Enscribe files.

For information about this capability, see Section 15, NonStop SQL/MX and RDF.

Zero Lost Transactions (ZLT)

Zero Lost Transactions (ZLT), which is available only with the RDF/ZLT product,

is a functional capability that uses mirrored disks to guarantee that no committed

transactions on the primary system will be lost in the event of an RDF takeover by the

backup system.

For information about this capability, see Section 16, Zero Lost Transactions (ZLT).

Monitoring RDF Entities With ASAP

ASAP (HP NonStop Availability Stats and Performance) allows many different

subsystem entities to be monitored across a network of HP NonStop servers. The

status and statistics for the entities are collected on a single system, and are then

monitored either through the ASAP command interface or through the ASAP graphical

user interface PC client.

RDF/IMP, IMPX, and ZLT are instrumented to feed state information to ASAP, thus

allowing RDF subsystems to be monitored, in an integrated way, alongside all other

subsystems supported by ASAP. The following RDF entities report state and statistical

information to ASAP:

•

Monitor

•

Extractor