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Introduction to TMF

HP NonStop TMF Management Programming Manual—540140-008

1-5

Database Tables and Files

You can use TMF to protect NonStop SQL/MP tables and Enscribe files.

Data Volumes

When configuring your TMF environment, you must identify all disk volumes that will

contain audited tables or files. These are referred to as data volumes.

To generate audit information, a database operation must occur within the bounds of a

TMF transaction and the table or file being manipulated must reside on a configured

TMF data volume.

Online Dumps

Online dumps are copies of audited database tables and files for use by the file

recovery process. If your database is damaged, the file recovery process can restore

online dump files to disk and then apply the restore-audit images to reconstruct the

database tables and files. Online dumps can be made while transactions are being

processed by your applications.

Recovery Processes

The TMF recovery processes are backout, volume recovery, and file recovery. They

are responsible for recovering from transaction, media, and system failures.

Backout

The TMF backout process undoes the effects of aborted transactions. It is created

when you start TMF and automatically invoked whenever a transaction aborts.

Volume Recovery

The TMF volume recovery process recovers data volumes that had one or more

tables or files open when a media or system failure occurred. It uses information in the

audit trail to back out transactions that were incomplete (not yet committed or aborted)

at the time of the failure. The TMF management process automatically invokes the

volume recovery process in response to START TMF and ENABLE DATAVOLS

commands or when a data volume comes up.

File Recovery

The TMF file recovery process uses online dumps (archived copies of database

tables and files) and audit dumps (archived copies of restore-audit files) to restore

tables and files to a consistent state after an accidental purge or a media failure. (File

recovery is also used to reorder a database to a previous date and time, after a

problem with the application occurs.) Volume recovery usually makes this

HP NonStop TMF User Manual

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