HP B6960-90078 manual Shared Devices in the SAN Environment

Configuring and Using Backup Devices

Shared Devices in the SAN Environment

Shared Devices in the SAN Environment

This section describes some of the basic concepts of Storage Area

Networks (SANs). For further conceptual information, see the HP

OpenView Storage Data Protector Concepts Guide.

The concepts and instructions provided here are the following:

•Device locking when the library is accessed exclusively by Data Protector

•Using the Data Protector user interface to configure the library robotics and drives

•Locking library robotics and drives

•Direct versus indirect library access

What Is a SAN? A Storage Area Network (SAN) is a network dedicated to data storage, based on high-speed Fibre Channel technology. A SAN lets you offload storage operations from application servers to a separate network. Data Protector supports this technology by enabling multiple hosts to share storage devices connected over a SAN, which allows multiple systems to be connected to multiple devices. This is done by defining the same physical device multiple times, for example, once on every system that needs access to the device.

Key Concepts There are some key concepts to consider when using Data Protector in a SAN environment:

•Each system can have its own (pseudo-)local device, although the devices are typically shared among several systems. This applies to individual drives, as well as to the robotics in libraries.

•Take care to prevent several systems from writing to the same device at the same time. Access to devices needs to be synchronized between all systems. This is done using locking mechanisms.

•SAN technology provides an excellent way of managing library robotics from multiple systems. It creates the ability to manage the robotics directly, as long as the requests sent to the robotics are synchronized among all the systems involved.

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