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

TMF Operations and Recovery Guide
HP NonStop TMF Supplement for Large Audit-Trail Files—527391-001
4-2
Reason: Required by RDF environment (Pages 2-6
through 2-7)
When you subsequently issue the START RDF command, RDFCOM asks TMF to
restore any necessary audit files from the archive media. However, if any of those
audit files are no longer available (because the online dumps that required them were
deleted by TMF RETAINDEPTH processing), RDF will be unable to start. In this case,
you must resynchronize the database protected by RDF.
There are two main disadvantages to using the UNPINAUDIT command: first, it
requires stopping RDF, thus removing substantial database protection until the
subsystem is restarted; second, it risks the need for database resynchronization, which
can involve substantial time and effort. Therefore, you might want to consider other
alternatives, such as:
•
Using the TMFCOM ALTER CATALOG command to increase the RETAINDEPTH
value for the TMF catalog. This action keeps the audit dumps available online for a
longer duration. A disadvantage, however, is that it allows the content of the
catalog to expand, consuming resources and potentially degrading performance
when TMF performs catalog operations.
•
Suspending the generation of online dumps. This action, like changing the
RETAINDEPTH value, keeps audit dumps available online longer. However,
subsequent RECOVER FILES operations must then process more files, again
affecting TMF performance.
For more information about the RDFCOM UNPINAUDIT command, see the RDF/IMP,
IMPX, and ZLT System Management Manual.