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

16 Understanding ISP
The benefits of ISP
Note: Products and features such as dynamic multipathing (DMP), RAID-5, SAL,
snapshots, and VAIL require licenses in addition to the base license.
This book describes the command-line interface to ISP, and the language that is
used for writing new rules, capabilities and templates. For a description of the
graphical interface to ISP that is provided by the VERITAS Enterprise
Administrator (VEA), see the VERITAS Enterprise Administrator User’s Guide
and VEA online help.
For more information about how you can apply ISP in different scenarios such
as implementing storage tiers, offhost processing, or remote mirroring between
different locations, see the Veritas Storage Foundation Intelligent Storage
Provisioning Solutions Guide.
The benefits of ISP
When creating a volume in Veritas Volume Manager in previous releases, you
could specify the disk storage on which to lay out its various parts, subdisks,
plexes, and so on. In specifying the storage to be used, you had to take into
account the tolerance of a volume to failure of any component of the storage
infrastructure, and how the specified layout affected I/O performance and
reliability of service. For small installations with a few tens of disks in relatively
low-specification arrays, you could either specify the storage layout manually to
commands such as vxassist, or rely on vxassist to choose appropriate
storage based on general layout specification, such as “mirror across
controllers” and “mirror across enclosures,” and using the set of heuristic rules
that were hard-coded within
vxassist.
The traditional model for allocating storage to volumes is shown in Figure 1-1.
This illustrates that, although some storage attributes are known to VxVM, you
must do most of the work in deciding how to lay out the storage if you are to
create a volume with the desired performance, reliability and fault tolerance.