TMF Reference Manual (G06.24+)

TMFCOM Commands
HP NonStop TMF Reference Manual—522418-002
3-57
ALTER AUDITTRAIL
When you expect to conduct many recovery operations at or near the same time, and
you wish to keep as many potentially required files on disk as possible, use the
MAXRETAINEDATFILES option. When the recovery load diminishes, use the RESET
MAXRETAINEDATFILES option to return to the standard restore-and-purge
mechanism for tape files, freeing disk space for other purposes. Remember:
MAXRETAINEDATFILES optimizes access time for files archived on tape; RESET
MAXRETAINEDATFILES maximizes available disk space.
To specify the amount of disk space available for retaining audit-trail files restored from
tape, use the MAXRETAINEDATFILES option to indicate this amount in terms of the
number of files. If you enter MAXRETAINEDATFILES while TMF is running, this option
takes effect immediately. If you enter MAXRETAINEDATFILES while TMF is stopped,
MAXRETAINEDATFILES takes effect when TMF restarts. The
MAXRETAINEDATFILES integer value specifies the number of audit-trail files to be
retained. This value applies only to the audit trail specified in the current ALTER
AUDITTRAIL command; TMF manages each audit trail individually with regard to its
MAXRETAINEDATFILES attribute.
The integer value specifies the total number of audit-trail files retained across the
entire set of restore-audit volumes. In other words, whether you have one restore-
audit volume or five restore-audit volumes, setting the value to 50 would give you a
maximum of 50 retained audit-trail files in either case.
The integer value does not affect the restored audit-trail files that are currently in use
by a recovery process, only what happens to those files when they are no longer in
use.
If you decrease integer from its current value, and the present number of retained
audit-trail files exceeds the new limit, TMF immediately purges the lowest-numbered
retained audit-trail files from disk until the new limit is reached. (For example, TMF
purges the files named AA000032 and AA000033 before AA000034.) If you increase
integer from its current value, TMF allocates no new space but does retain more
audit-trail files from this moment on, until the currently allocated space runs out.
If you set the integer value too high, attempts by a recovery process to restore
required audit-trail files may fail with File System Error 43. In this case, you can
correct the problem without restarting the recovery operation by taking any of these
actions:
•
Lower the MAXRETAINEDATFILES value.
•
Free more restore-audit-volume disk space.
•
Add more restore-audit volumes to the TMF configuration.
Before using the MAXRETAINEDATFILES option, be sure that enough space actually
exists on the restore-audit volumes to contain the restored audit dumps. This
precaution is particularly important where restore-audit volumes overlap between
configured audit trails.