TMF Planning and Configuration Guide (H06.05+)

Reconfiguring Audit Trails
HP NonStop TMF Planning and Configuration Guide540136-002
3-4
Number of Active-Audit Volumes
Number of Active-Audit Volumes
An active-audit volume is a disk volume configured to contain active audit-trail files. An
active-audit volume cannot also be configured as a data volume.
For G-series releases only, the TMF product is shipped from the factory with the
$AUDIT disk volume configured as the active-audit volume. You are free to retain
$AUDIT for this purpose, replace $AUDIT with another volume as the recipient of audit
trails, or add other active-audit volumes to the configuration. See also the information
about the preconfiguration of data volumes for G-series releases, under Adding Data
Volumes on page 2-4.
How Multiple Active-Audit Volumes Are Used
You can add or delete active-audit volumes while transaction processing is in progress.
If you configure more than one active-audit volume for an audit trail, they are used in
alternating sequence for storing audit-trail files. For example, if you configure two
active-audit volumes named $A and $B, the first audit-trail file will be stored on volume
$A, the second on volume $B, the third on volume $A, and so forth. This method of
disk usage ensures that, under normal circumstances, the audit dump process reads
from a different physical disk drive than the one containing the current audit-trail file,
thereby avoiding disk head contention and excessive seeks.
Adding Active-Audit Volumes
Adding an active-audit volume increases the audit-trail capacity by the number of files
configured to reside on each volume of an audit trail. If there is not enough disk space
for these files, the volume cannot be added.
Deleting Active-Audit Volumes
Deleting an active-audit volume decreases the audit-trail capacity by the number of
files configured to reside on each volume of an audit trail. For at least a week, keep a
record of the level of audit-trail capacity used before deleting an active-audit volume.
Make sure that decreasing the audit-trail capacity will not cause frequent overflow
conditions.
If you delete a volume that contains files needed by a TMF process, the volume
remains in the configuration until it has no active audit-trail files. No further audit
records are written to this volume, and any preallocated files on the volume are
deleted.
Note. If you wish to increase the capacity of an audit trail by adding an active-audit volume,
first check that the need for additional capacity is not caused by a too-low setting of the
overflow threshold, as described in Changing the Overflow Threshold on page 3-8.
Note. To delete an active-audit volume, you must have more than one active-audit volume
configured. If you have only one active-audit volume, you cannot delete it, and an explicit
rollover always rolls over to the same volume.