13 Snapshot concepts

In this chapter

This chapter introduces the snapshot backup concepts and discusses the configurations that are supported by HP.

It is organized as follows:

“Overview” on page 275F

“Supported configurations” on page 281

Overview

The rapidly expanding requirement for high availability storage configurations has led to the introduction of new zero downtime backup (ZDB) technologies. The advances in storage virtualization technology have provided the opportunity for an alternative to conventional split mirror technology.

Within the Data Protector ZDB solution, different disk array technologies are combined with the latest developments in the snapshot technology, to create snapshots of application or database data stored on a disk array. These snapshots can subsequently be kept on a disk array as point-in-time copies of the original data for instant recovery purposes or can be used to produce ZDB-to-tape sessions on a backup system. The processes concerned have minimal impact on the application server, providing an effective ZDB solution.

Storage virtualization

The term “storage virtualization” is used to describe the technology that separates the logical representation of storage from the actual physical storage components. This means the creation of logical volumes out of a pool of physical disks residing in a disk array. A logical volume is limited by the boundaries of the pool, but may span over any number of physical disks within the disk array. Logical volumes can be presented to one or multiple host systems. You cannot have control over the exact

Concepts guide

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