Veritas Storage Foundation Intelligent Storage Provisioning 5.0 AdministratorÆs Guide, HP-UX 11i v3, First Edition, May 2008

213Examples of using ISP

Segregating database components

To achieve best performance, it is usual to place the components of a database,

such as the redo log, table spaces and indexes, on different disks. This can be

accomplished by using the disk tagging feature, which allows you to define new

characteristics and then assign these to your disks.

Note: The disk tagging may be accessed by selecting a disk in the Veritas

Enterprise Administrator, and then selecting Actions > Annotate Disks. This

feature is also available from the command line by using the

vxdisk settag

command. See the vxdisk(1M) manual page for more information.

Disk tagging can be used in conjunction with volume rules to reserve disks for

particular volumes. By tagging disks with a suitable attribute name and value

such as reserved_for and redo_log, you can use a confineto rule to

ensure that the volume for a redo log is only allocated space from those disks:

confineto "reserved_for"="redo_log"

Conversely when creating volumes that are not to be used for the redo logs, you

can specify an exclude rule:

exclude "reserved_for"="redo_log"

This technique allows you to share appropriately tagged disks among a set of

volumes of the same type. For example, if you specify the same confinement rule

when creating several redo log volumes in a storage pool, those volumes share

the disks that are reserved for that purpose.