3.12. HPSS Metadata Back up Considerations
This section contains guidelines for proper maintenance of the HPSS metadata st ored in DB2.
The policies described should be fully understood and implemented to protect the HPSS
metadata. Failure to follow these policies can lead to unrecoverable data loss.
The remainder of this section is a set of rules associated with backing up HPSS metadata. Though
automated archive software like Tivoli Storage Manager is used to backup and protect DB2 data, it is
important that each site review this list of rules and check to ensure that their site's backup is
consistent with these policies.
When deciding on the size and number of disks for metadata, keep in mind the following:
1. At a minimum, for subsystem-specific metadata, the disks hosting the DB2 instance
installation path (i.e the home directory of the instance owner) and the databases' tablespaces
should be separate. This is not critical for configuration metadata s ince it changes
infrequently.
2. Ideally, several physical disks should be available for DB2 tablespaces (namespace data can
be on one, bitfile data on another, etc.).
3. If the backup software employed involves some sort of disk staging area, this should be on a
separate disk, and a large amount of disk should be allocated for this purpose.
For reliability and availability reasons, the disk hosting the instance instal lation data should be
mirrored. The disks hosting the tablespaces should also be mirrored if possible. For performance and
reliability reasons, mirroring should be done using separate physical devices (as opposed to the AIX
logical volume being mirrored to the same physical drive).
3.13. HPSS Security Cons iderations
The security requirements between sites differ widely. The HPSS System Administrators must be
aware of the sites security requirements and should be aware of the security configur ation required in
HPSS. Sites should contact their site representative if they have questions rega rding HPSS security.
For more information on security, see Chapter 2: Security and System Access of the HPSS
Management Guide.
HPSS Installation Guide July 2008
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