IBM DS8000 manual Tor

16.1 Introduction

The term data migration has a very diverse scope. We use it here solely to describe the process of moving data from one type of storage to another, or to be exact, from one type of storage to a DS8000. In many cases, this process is not only comprised of the mere copying of the data, but also includes some kind of consolidation.

With our focus on storage, we distinguish three kinds of consolidation, also illustrated in Figure 16-1:

￿The consolidation of distributed, direct-attached storage to shared, SAN-attached disk storage

￿The consolidation of many small volumes into a few larger ones

￿The consolidation of several small storage systems into a few larger ones

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Collection of small volumes

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Figure 16-1 Different ways of consolidation

Very often, the set goal of a consolidation effort is a combination of more than one of these types. The DS8000, with its exceptional scalability and performance, makes an ideal target system for storage consolidation.

There are many different methods for data migration. To decide what is best in your case, gather information about the following items:

￿The source and target storage make and type

￿The amount of data to be migrated

￿The amount of time available for the migration

￿The ability to connect both source and target storage at the same time

￿The availability of spare disk or tape capacity for temporary storage

￿The format of the data itself

￿The consolidation goals

￿Can the migration be disruptive, and for how long

￿The distance between source and target

334DS8000 Series: Concepts and Architecture