TMF Supplement for Large Audit Files (G06.24+)

TMF Planning and Configuration Guide
HP NonStop TMF Supplement for Large Audit-Trail Files—527391-001
3-4
Fallback From a Format 2 Audit-Trail Environment to
a Format 1 Audit-Trail Environment (Appendix A)
If there is more room on the active-audit volume, increase the number of files per
active-audit volume. If the active-audit volume is fully allocated, add another active-
audit volume.
Note that when you add an active-audit volume, the audit-trail capacity is increased by
the current configured number of files per active-audit volume.
TMF automatically aborts (backs out) transactions based on master audit-trail capacity.
If 45% of the total MAT capacity is consumed during a transaction, that transaction is
aborted.
The 45% value cannot be changed in the configuration. If this feature causes TMF to
abort transactions that should not be aborted, you must increase the audit-trail capacity
by either increasing the number of audit-trail files per volume or by adding another
active-audit volume. When the additional audit-trail space is no longer needed, you
can reduce the audit trail to its original size.
In addition, TMF has an autoabort threshold based on a configurable transaction
timeout value.
If any audit-trail sequence number is 900,000 or more, TMF must be stopped and re-
configured with larger audit-trail sizes in the near future. TMF will stop abruptly, and
cannot be restarted when a sequence number reaches 999,999.
Fallback From a Format 2 Audit-Trail
Environment to a Format 1 Audit-Trail
Environment
(Appendix A)
With respect to TMF, the ability to fall back to an RVU that only supports format 1
audit-trail files is analogous to the old RVU’s (whatever RVU you migrated from) ability
to read and comprehend the new format 2 audit-trail files. The new format 2 files have
some new versions of audit records since RBA fields had to be extended to INT(64) in
those records. If you migrated to an RVU that supports format 2 audit-trail files, but are
still using format 1 audit-trail files, there are no issues with fallback because the old
RVU can interpret the format 1 audit-trail files.
After you use the TMFCOM command to transition to format 2 files, however, then
fallback may not be possible without a DELETE TMF because the old RVU cannot
read the new format 2 audit-trail files. If fallback is essential, you should attempt to get
the database in the best possible state. If fallback can be scheduled, you might be able
to transition back out of format 2 into format 1 files prior to falling back. However, once
you go to format 2 at all, to fall back without a DELETE TMF is complicated. The topics
that follow describe the time line for migration and transition to format 2, and the
fallback plan appropriate given the situation.