General Considerations; The Ds6000 Host Systems Attachment Guide; Planning - IBM TotalStorage DS6000 Series Redbooks

General considerations

In this section we cover some topics that are not specific to a single operating system. This
includes available documentation, some planning considerations, and common tools.

The DS6000 Host Systems Attachment Guide

The DS6000 Host Systems Attachment Guide, SC26-7680, provides instructions to prepare a
host system for DS6000 attachment. For all supported platforms and operating systems it
covers:
Installation and configuration of the FC HBA
Peculiarities of the operating system with regard to storage attachment
How to prepare a system that boots from the DS6000 (when supported)
It varies in detail for the different platforms. Download it from:
http://www.ibm.com/servers/storage/disk/ds6000
Many more publications are available from IBM and other vendors. Refer to
"Open systems support and software" on page 275
sections in this chapter.

Planning

Thorough planning is necessary to ensure that your new DS6000 will perform efficiently in
your data center. In this section we raise the questions you will have to ask and the things you
have to consider before you start. We don't cover all the items in detail because this is not an
implementation book.
For a more detailed discussion of these considerations related to performance refer to
Chapter 11, "Performance considerations" on page 219.
Capacity planning considerations
For proper sizing of your DS6000 storage subsystem more than the total required capacity
has to be known. Consider the following questions:
What is the capacity for each host system or even each application? What are this
system's performance requirements (I/Os, throughput)?
How much capacity is needed for fixed block (open systems) and how much for CKD
(mainframe) data?
Do you need advanced copy functions?
What is the number of disk drives needed, their size and speed?
With the usable capacity known, what is the raw capacity to order?
What is the number of Fibre Channel attachment needed?
Do you have to plan for future expansion?
Data placement considerations
A DS6000 logical volume is composed of
an array (or rank, which is equivalent). To create the logical volume, extents from one extent
pool are concatenated. Within a given extent pool there is no control over the placement of
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DS6000 Series: Concepts and Architecture
and to the operating system-specific
extents
. These extents are striped across all disks in
Chapter 14,