Configuring and Using Backup Devices

Shared Devices in the SAN Environment

Direct Library Access Concept

With direct library access, every system sends control commands directly to the library robotics. Therefore, a system does not depend on any other system in order to function.

With direct library access , when multiple systems send commands to the same library, the sequence of such communication has to be coordinated. Therefore, every library definition is associated by default with a host controlling the library robotics. If another host requests that a medium be moved, Data Protector will first access the system specified in the library definition for performing the move. If the system is not available, direct access from the local host to the library robotics is used if the libtab file is set. All of this is done in a transparent manner within Data Protector.

Indirect Library Access Concept

With indirect library access, only one system (the default robotics control system) sends robotic control commands that are initiated from Data Protector. Any other system that requests a robotics function forwards the request to the robotics control system, which then sends the actual command to the robotics. This is the default setting, and is done in a transparent manner within Data Protector for all requests from Data Protector.

Configuration Overview

This section provides an overview of the steps involved in configuring your system. It includes the following topics:

•Configuration goals

This section specifies the mixed SAN environment to be configured.

•Configuration methods

This section outlines the configuration methods that need to be performed for UNIX, Windows, and mixed SAN environments.

•Autoconfiguring the devices

This section outlines the device autoconfiguration specifics in a SAN environment.

•Manually configuring the robotics

Chapter 2

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