Key Concepts

A tape library consists of a media changer, one or more tape drives, and many tape slots. The media changer inserts and removes tapes from the tape drives. The tape drives read data from and write data to tapes. The tape slots store tapes.

The tape library is attached to your Enterprise either directly or through a Storage Area Network). The tape library could be directly attached to an NDMP-compliant NAS appliance that is connected to the Enterprise.

For a given tape library, each tape drive and the media changer need to communicate with a computer, or node, in the Enterprise. A node that communicates with a tape drive is referred to as a device server. The node that communicates with and controls the media changer is referred to as the controller node. (A controller node is a special type of a device server.) The following diagram illustrates these concepts:

For the tape drives, drivers are supplied by the tape drive manufacturers. Work with the manufacturer to install those drivers.

For the media changer, the media changer device file is supplied by DPX as described in Chapter 35: Manual Tape Library Installation. Install the media changer device file on the controller node, enabling DPX to communicate with and control the media changer.

The media changer device file for a tape library is installed on a single controller node. If your tape library is connected via a Storage Area Network (SAN), the media changer device file still needs to be installed on only one controller node, even though the SAN may contain many device servers. If the tape library is attached to an NDMP-compliant NAS appliance, you do not have to install a media changer device file, but you do need to perform tape library configuration. See Chapter 37: Overview of Manual Tape Library Configuration.

Tape libraries, media changers, and tape drives are sometimes referred to by different names, as shown in the following table:

Term (used in this manual)	Synonyms
Tape Library	Tape library; Automated tape library; Library server
Media Changer	Media changer device
Tape drive	Tape device; Storage device; Tape Library device

Note that during the tape library setup process, when you are asked to provide information (such as the Target ID) for a tape library, you need to provide the information that applies to the media changer, not the tape drives.