TMF Reference Manual (G06.26+)

TMFCOM Commands
HP NonStop TMF Reference Manual—522418-003
3-20
ADD AUDITTRAIL
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When new audit-trail files are preallocated, TMF creates them with the configured
file size for the specified audit trail and the format value currently in effect for the
TMF configuration. (Always remember that while the FILESIZE value applies to a
specific audit trail, the ATFORMAT value entered through the ALTER TMF
command applies to your entire TMF configuration.)
FILESPERVOLUME Option Considerations
TMF uses the FILESPERVOLUME value to pre-allocate the number of files in the
active-audit trail that reside on each volume; if they cannot all be allocated, the ADD
AUDITTRAIL command fails. You can change the FILESPERVOLUME value by using
the ALTER AUDITTRAIL command, whether TMF is started or not.
TMF calculates disk extent size on the basis of 16 extents per file, with all extents (both
primary and secondary) being the same size.
OVERFLOWVOL and OVERFLOWTHRESHOLD Option
Considerations
Overflow-audit volumes are used to store files when the active-audit trail becomes too
full. At this point, the oldest audit-trail files are copied to the overflow volumes so that
the space occupied by these audit-trail files can be reused. In the OVERFLOWVOLS
parameter, you can specify the overflow-audit volumes you want TMF to use for this
purpose. In the OVERFLOWTHRESHOLD parameter, you can specify the capacity
level of the active-audit trail that will trigger overflow copying. For example, if you want
overflow copying to begin when 95% of the available audit trail space has been used,
set OVERFLOWTHRESHOLD to 95. The time it takes to reach the overflow threshold
depends on the audit generation rate and the total audit trail capacity.
Once overflow copying begins, it continues until the capacity used falls below the
threshold, even though space subsequently becomes available on the active-audit
volume. When they are no longer needed, overflow files are automatically purged by
TMF.
Note. You should ensure that enough disk space exists to accommodate files of the size
specified in FILESIZE and the number specified in FILESPERVOLUME. If the disk has
insufficient space in which to create a new file of the latest configured FILESIZE, TMF simply
renames the existing file even though that file may be of improper size or format, and keeps
the configuration in a transition state; in this state, files of different sizes continue to exist.