IBM TS4500, Introduction And Planning Manual, Page: 61 / 218

commands to control the logical library. For frames that contain LTO tape drives
and frames that contain 3592 tape drive, each logical library control path is
available to servers through logical unit number (LUN) 1 of the first drive that is
defined within that logical library. A LUN is a number that is used by a server to
identify a drive.
In a TS4500 tape library, a logical library shares empty storage slots, empty I/O
slots, and the cartridge accessor on a first-come, first-served basis.
Note: When you are naming logical libraries, developing an enterprise-wide
library naming convention leads to easier management of the libraries.
With automatic cleaning, cleaning cartridges are shared between logical libraries,
so any appropriate cleaning cartridge is used to clean a drive in any configured
logical library.
Share libraries by using multiple logical libraries
Partition a TS4500 tape library into multiple logical libraries to enable simultaneous
data backup and restore tasks from different applications.
You can partition the library so that it processes:
v
Commands from Application 1 (about Department A) in Logical Library 1
v
Commands from Application 2 (about Department B) in Logical Library 2
v
Commands from Application 3 (about Department C) in Logical Library 3
In this configuration, the tape drives and cartridges of each logical library are
dedicated to that library and are not shared among other libraries. Commands that
are issued by the applications travel to the library through three unique control
paths. So, the data processing for Department A is confined to the tape drives and
cartridges of Logical Library 1. Processing for Department B is confined to the tape
drives and cartridges of Logical Library 2, and so forth.
Multiple logical libraries for mixed drive types
For applications that do not support mixed drive types and media within the same
logical library, the TS4500 tape library can partition the applications.
The TS4500 tape library places the applications into multiple logical libraries to
keep them separate.
For example, you can partition the following tape drives and their media into
multiple and separate logical libraries:
v
LTO 8
v
LTO 7
v
LTO 6
v
LTO 5
Multiple control paths
You can configure any TS4500 tape library logical library to have multiple control
paths.
With the TS4500 tape library, in addition to creating multiple logical libraries, you
can configure any logical library to have more than one control path. When you
configure more control paths, more library-sharing configurations and options are
Chapter 1. Overview
43