IBM High Performance Storage System HPSS Installation Manual Download

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created will require approximately 10MB of disk space in a filesystem that should be used only for
database home directories and other DB2 home directories (such as the DB2 Administration Server
and Fenced User). This filesystem should be protected by RAID since DB2 may require information
in the database home directory to properly recover a database.

DB2 backups

Full backups of DB2 databases may be larger than the databases themselves. The amount of local
disk space needed for backups will depend largely on the backup strategy.

When using the DB2 to TSM strategy, local disk is not needed to backup DB2 databases. DB2
communicates directly with the TSM API to deliver backup images and archived log files directly to
TSM. This strategy is highly recommended.

3.5.5. System Memory and Disk Space

The following sections discuss recommendations and requirements for disk space, system memory,
and paging space.

3.5.5.1. Operating System Disk Spaces

It is recommended that all operating system logical volumes/partitions be mirrored. This is true of
the HPSS server and Mover nodes. Both AIX and Linux support this type of configuration.

3.5.5.2. System Disk Space Requirements for Running SSM

The SSM Graphical User Interface,

hpssgui

, and Command Line Interface,

hpssadm

, have an option

to create session log files.

hpssgui

records all status bar and popup messages issued during the

session in its log.

hpssadm

records all prompts, error and informational messages, and requested

output (lists, managed objects, configuration structures, etc.) issued during the session in its log. Old
session log files should be removed periodically to avoid filling the file system. This is typically
done with a

cron

job. For example, the following command will remove all files from

/tmp

which

have not been accessed within the previous seven days:

% find /tmp -atime +7 -exec rm {} \;

The creation of the session log files is controlled by the -S option to the hpssgui and hpssadm startup
scripts. See their man pages for details.

3.5.5.3. System Memory and Paging Space Requirements

The memory and disk space requirements for the nodes where the HPSS Servers will execute
depends on the configuration of the servers, the nodes that each server will run on, and the amount
of concurrent access they are configured to handle.

At least 2GB of memory is recommended for nodes that will run one or more HPSS servers (and most
likely a DB2 server), excluding the HPSS Movers. More memory is required for systems that run
most of the servers on one node and/or support many concurrent users. The memory available to
HPSS and DB2 servers is critical to providing acceptable response times to end user operations. Disk
space requirements are primarily covered by Section 3.5.4:

HPSS Metadata Space

on page 74 for

DB2 space, and the preceding subsections under Section 3.5.5:

System Memory and Disk Space

page 78 for the individual HPSS servers. Sufficient disk space should be allocated for the paging
space, using recommendations in the system documentation for the amount of memory configured.

HPSS Installation Guide

July 2008

Release 6.2 (Revision 2.0)