Introduction to TMF
HP NonStop TMF Management Programming Manual—540140-008
1-5
Database Tables and Files
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
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