TMF Planning and Configuration Guide (H06.05+)

Reconfiguring Audit Trails
HP NonStop TMF Planning and Configuration Guide—540136-002
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Number of Overflow-Audit Volumes
To delete the volume that contains the current audit-trail file or the next audit-trail file to
receive audit information, you must first initiate a rollover by issuing one or more NEXT
AUDITTRAIL commands. An audit dump occurs automatically after the rollover, but
you must wait until the audit dump is completed (as indicated in the event log) before
you delete the volume.
Number of Overflow-Audit Volumes
An overflow-audit volume is a disk volume configured to store audit-trail files when the
active audit trail becomes too full. In the overflow threshold attribute, you specify the
capacity level of the active audit trail that will trigger TMF to use the overflow space.
Any volume can be configured as an overflow-audit volume, including volumes
configured for other TMF purposes.
Adding an overflow-audit volume increases the space available for overflow-audit files.
If you have operational problems because audit-trail space has run out, you can solve
the problem temporarily by adding another overflow-audit volume, then check for and
correct the cause of the high use of audit-trail space. You can add or delete overflow-
audit volumes while transaction processing is in progress.
The total recommended number of overflow-audit volumes depends on their size. You
should configure enough overflow-audit volume space to store all the files you believe
will overflow; if you’re unsure, err on the side of too much space. Configuring overflow-
audit volumes costs nothing; no overflow space is allocated until it is needed, and
meanwhile the space can be used for other purposes. However, you should configure
TMF so that your application rarely uses overflow space. If your application regularly
uses overflow space, consider increasing space in the audit trail by increasing the files
per active-audit volume or adding an active-audit volume.
Deleting an overflow-audit volume decreases the space available for overflow-audit
files. If your application regularly uses overflow space, deleting an overflow-audit
volume might cause the audit trail to reach its begin-transaction-disable threshold,
thereby causing transaction processing to stop.
If you delete an overflow-audit volume that contains files needed by a TMF process,
the files remain on the volume until they are not needed. No further overflow-audit files
are written to this volume after it is successfully deleted from the audit-trail
configuration.
Number of Restore-Audit Volumes
A restore-audit volume is a disk volume used to receive audit-trail files restored from
an audit dump as part of a recovery procedure. Any volume can be configured as a
restore-audit volume, including volumes configured for other TMF purposes.
Adding a restore-audit volume increases the space available for restoring audit dumps
during a recovery procedure. You can add or delete restore-audit volumes while
transaction processing is in progress.