SQL/MX 2.x Installation and Management Guide (G06.24+, H06.03+)

Planning Database Security and Recovery
HP NonStop SQL/MX Installation and Management Guide—523723-004
5-7
Database Recovery Guidelines
Database Recovery Guidelines
When planning backup strategies, consider these guidelines:
Topic Guideline
SQL/MX subvolume
and file naming
guidelines
In planning database recovery, it is important to properly follow
the rules for naming SQL/MX subvolumes and files. For
information, see SQL/MX Subvolume Naming Guidelines
on
page 7-2.
Using Guardian
names with TMF,
RDF, and Measure
For NonStopn SQL/MX Release 2.1 or Release 2.0, the user
interfaces to the TMF, RDF, and Measure subsystems require
Guardian physical file names instead of ANSI logical names.
Use the MXGNAMES utility to generate the portions of the
subsystem command lines that contain Guardian file names.
For information about using MXGNAMES, see Appendix B,
Using Guardian Names With TMF, RDF, and Measure.
Audited files All SQL/MX files are audited. Therefore, use TMF online dumps
as the primary method for preserving SQL/MX objects, as
described in Using TMF for Transaction Recovery, Database
Consistency, and Database Recovery on page 5-10. Preserving
files by using BACKUP is not effective for recovery if any files
are open during the backup operation. Even if you use the
OPEN option, the image saved during the dump of the database
might not be consistent.
Tape management If your system has only one tape drive, be careful not to perform
a long backup at a time when the TMF subsystem might also
need to dump an audit trail to tape. Before starting the backup,
verify the status of the TMF audit trails to make sure no dump is
currently queued. If the TMF subsystem reaches its maximum
file limit during a period when the tape drive is unavailable for
audit trail dumping, the TMF subsystem suspends transaction
processing until an audit trail is dumped.
If your system has multiple tape drives, you can use one drive
for backups and another for the TMF audit-trail dumps.
Backup and Restore 2 has many options that can filter the
objects backed up or restored, improve the performance of tape
handling, ignore errors, and verify tape validity. For information
about these options, see the Backup and Restore 2 Manual.
Unreclaimed free
space
Determine if you want to make INCOMPLETE SQLDDL
OPERATION a separate line item or include it in the Topic
paragraph with Unreclaimed free space. You may also want to
add a reference to where these flags are described.
If an SQL/MX object has the UNRECLAIMED FREESPACE (F)
or INCOMPLETE SQLDDL OPERATION (D) attribute set, do
not attempt to back up, move, or duplicate the object until the
attribute is reset.